Display device

ABSTRACT

A display device includes a first pixel including a first light emitting area in which first light emitting elements are arranged, a second pixel including a second light emitting area in which second light emitting elements are arranged, a light blocking pattern disposed on the first and second pixels to overlap a peripheral area of the first and second light emitting areas and including a first opening corresponding to the first light emitting area and a second opening corresponding to the second light emitting area, and a color filter including a first color filter pattern disposed in the first opening and a second color filter pattern disposed in the second opening. The second pixel includes a greater number of second light emitting elements than a number of the first light emitting elements. The second opening has an area smaller than an area of the first opening.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to and benefits of Korean PatentApplication No. 10-2020-0080592 under 35 U.S.C. § 119, filed on Jun. 30,2020 in the Korean Intellectual Property Office, the entire contents ofwhich are incorporated herein by reference.

BACKGROUND 1. Technical Field

An embodiment relates to a display device, and to a display deviceincluding a light emitting element.

2. Description of the Related Art

Recently, interest in information display is increasing. Accordingly,research and development of a display device has been continuouslyconducted.

It is to be understood that this background of the technology sectionis, in part, intended to provide useful background for understanding thetechnology. However, this background of the technology section may alsoinclude ideas, concepts, or recognitions that were not part of what wasknown or appreciated by those skilled in the pertinent art prior to acorresponding effective filing date of the subject matter disclosedherein.

SUMMARY

An object of the disclosure is to provide a display device including alight emitting element.

A display device according to an embodiment may include at least onefirst pixel each including a first light emitting area in which firstlight emitting elements may be arranged; at least one second pixel eachincluding a second light emitting area in which second light emittingelements may be arranged; a light blocking pattern disposed on the atleast one first pixel and the at least one second pixel to overlap aperipheral area of the first light emitting area and the second lightemitting area, the light blocking pattern including a first openingcorresponding to the first light emitting area of the at least one firstpixel and a second opening corresponding to the second light emittingarea of the at least one second pixel; and a color filter including afirst color filter pattern disposed in the first opening of the lightblocking pattern; and a second color filter pattern disposed in thesecond opening of the light blocking pattern. The at least one secondpixel may include a greater number of the second light emitting elementsthan a number of the first light emitting elements of the at least onefirst pixel. The second opening of the light blocking pattern may havean area smaller than an area of the first opening of the light blockingpattern.

In an embodiment, each of the first opening and the second opening ofthe light blocking pattern may have a shape extending along a firstdirection, and the second opening of the light blocking pattern may havea length shorter than a length of the first opening of the lightblocking pattern in the first direction.

In an embodiment, the first color filter pattern and the second colorfilter pattern may have a same color and may have a shape extendingalong the first direction, and the second color filter pattern may havea length shorter than a length of the first color filter pattern in thefirst direction.

In an embodiment, the second color filter pattern may have an areasmaller than an area of the first color filter pattern.

In an embodiment, the first light emitting elements and the second lightemitting elements may emit light of a same color.

In an embodiment, the display device may further include a first colorconversion pattern layer disposed on the at least one first pixel andthe at least one second pixel and including first color conversionparticles that may convert light emitted from the first light emittingelements and the second light emitting elements into light of a firstcolor.

In an embodiment, the display device may include the at least one firstpixel may include a plurality of first pixels including first lightemitting elements arranged in each first light emitting area of theplurality of first pixels, and the at least one second pixel may includea plurality of second pixels including second light emitting elementsarranged in each second light emitting area of the plurality of secondpixels.

In an embodiment, the plurality of first pixels may include at least onefirst color first pixel, at least one second color first pixel, and atleast one third color first pixel, and the plurality of second pixelsmay include at least one first color second pixel, at least one secondcolor second pixel, and at least one third color second pixel.

In an embodiment, the first color second pixel may include second lightemitting elements of a greater number than a number of first lightemitting elements arranged in the first color first pixel, and the lightblocking pattern may include an opening of a smaller area on the firstcolor second pixel than an opening of an area on the first color firstpixel.

In an embodiment, the display device may include at least one pixelblock including a plurality of pixels arranged along a second direction,and the at least one pixel block may include first pixels disposed atends of the at least one pixel block; and second pixels disposed betweenthe first pixels disposed at the ends of the at least one pixel block inthe second direction.

In an embodiment, the at least one pixel block may include a pluralityof pixel blocks, and the display device may include a display area inwhich the plurality of pixel blocks may be arranged.

In an embodiment, the light blocking pattern may include first openingsdisposed on each of the first pixels; and second openings disposed oneach of the second pixels and having an area smaller than an area ofeach of the first openings of the light blocking pattern.

In an embodiment, the color filter may include a first color first colorfilter pattern disposed on a first color first pixel among the firstpixels; and a first color second color filter pattern disposed on afirst color second pixel among the second pixels.

In an embodiment, the first color second color filter pattern may havean area smaller than an area of the first color first color filterpattern.

According to an embodiment, a luminance deviation of pixels may bereduced or prevented by adjusting an aperture ratio of the pixelsaccording to a number deviation of light emitting elements. Accordingly,image quality of the display device may be improved.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the disclosure will become more apparentby describing in further detail embodiments thereof with reference tothe accompanying drawings, in which:

FIGS. 1A and 1B are a perspective view and a schematic cross-sectionalview illustrating a light emitting element according to an embodiment;

FIG. 2 is a plan view illustrating a display device according to anembodiment;

FIG. 3 is an equivalent circuit diagram illustrating a pixel of thedisplay device according to an embodiment;

FIGS. 4A and 4B are plan views illustrating pixel of the display deviceaccording to an embodiment, respectively;

FIGS. 5A and 5B are schematic cross-sectional views illustrating thepixel of the display device according to an embodiment, respectively;

FIGS. 6 and 7 are a plan view and a schematic cross-sectional viewillustrating a method of supplying the light emitting elements to thepixels according to an embodiment;

FIG. 8 is a plan view illustrating a pixel block according to anembodiment;

FIG. 9A is a plan view illustrating a first pixel of FIG. 8;

FIG. 9B is a plan view illustrating a second pixel of FIG. 8;

FIGS. 10A to 10E are plan views each illustrating a color filter and alight blocking pattern according to an embodiment;

FIGS. 11A and 11B are schematic cross-sectional views each illustratingthe display device according to an embodiment; and

FIGS. 12A and 12B are schematic cross-sectional views illustrating thedisplay device according to an embodiment, respectively.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The disclosure may be modified in various ways and may have variousforms, and embodiments will be illustrated in the drawings and describedin detail herein. In the following description, the singular forms alsoinclude the plural forms unless the context clearly includes thesingular.

The disclosure is not limited to the embodiments disclosed below, andmay be modified and implemented in various forms. For example, each ofthe embodiments disclosed below may be implemented alone or incombination with at least one of other embodiments.

In the drawings, some components which may not be directly related to acharacteristic of the disclosure may be omitted for clarity andconvenience. For example, some components in the drawings may be shownto be exaggerated in size or proportion for ease of description and forclarity. Throughout the drawings, the same or similar components will begiven by the same reference numerals and symbols as much as possibleeven though they may be shown in different drawings, and repetitivedescriptions may be omitted.

The terms “and” and “or” may be used in the conjunctive or disjunctivesense and may be understood to be equivalent to “and/or.” In thespecification and the claims, the phrase “at least one of” is intendedto include the meaning of “at least one selected from the group of” forthe purpose of its meaning and interpretation. For example, “at leastone of A and B” may be understood to mean “A, B, or A and B.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, these elements should notbe limited by these terms. These terms are only used to distinguish oneelement from another element. Thus, a first element discussed belowcould be termed a second element without departing from the teachings ofthe disclosure.

As used herein, the singular forms, “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

It will be further understood that the terms “comprises” and/or“comprising”, “includes” and/or “including”, “has or have” and/or“having” and their variations when used in this specification, specifythe presence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

In the disclosure, it will be understood that when an element or layeris referred to as being “on”, “connected to” or “coupled to” anotherelement or layer, it may be directly on, connected or coupled to theother element or layer or intervening elements or layers may be present.

The spatially relative terms “below”, “beneath”, “lower”, “above”,“upper”, or the like, may be used herein for ease of description todescribe the relations between one element or component and anotherelement or component as illustrated in the drawings. It will beunderstood that the spatially relative terms are intended to encompassdifferent orientations of the device in use or operation, in addition tothe orientation depicted in the drawings. For example, in the case wherea device illustrated in the drawing is turned over, the devicepositioned “below” or “beneath” another device may be placed “above”another device. Accordingly, the illustrative term “below” may includeboth the lower and upper positions. The device may also be oriented inother directions and thus the spatially relative terms may beinterpreted differently depending on the orientations.

Additionally, the terms “overlap” or “overlapped” mean that a firstobject may be above or below or to a side of a second object, and viceversa. Additionally, the term “overlap” may include layer, stack, faceor facing, extending over, covering or partly covering or any othersuitable term as would be appreciated and understood by those ofordinary skill in the art. The terms “face” and “facing” mean that afirst element may directly or indirectly oppose a second element. In acase in which a third element intervenes between the first and secondelement, the first and second element may be understood as beingindirectly opposed to one another, although still facing each other.When an element is described as ‘not overlapping’ or ‘to not overlap’another element, this may include that the elements are spaced apartfrom each other, offset from each other, or set aside from each other orany other suitable term as would be appreciated and understood by thoseof ordinary skill in the art.

The phrase “in a plan view” means viewing the object from the top, andthe phrase “in a schematic cross-sectional view” means viewing across-section of which the object is vertically cut from the side.

“About” or “approximately” as used herein is inclusive of the statedvalue and means within an acceptable range of deviation for theparticular value as determined by one of ordinary skill in the art,considering the measurement in question and the error associated withmeasurement of the particular quantity (i.e., the limitations of themeasurement system). For example, “about” may mean within one or morestandard deviations, or within ±30%, 20%, 10%, 5% of the stated value.

As used herein, the term “unit” and/or “module” denotes a structure orelement as illustrated in the drawings and as described in thespecification. However, the disclosure is not limited thereto. The term“unit” and/or “module” is not to be limited to that which is illustratedin the drawings.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It willbe further understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein.

FIGS. 1A and 1B are a perspective view and schematic cross-sectionalviews illustrating a light emitting element LD according to anembodiment. For example, FIG. 1A illustrates an example of the lightemitting element LD that may be used as a light source of a pixelaccording to an embodiment, and FIG. 1B illustrates an example of across-section of the light emitting element LD along a line I˜I′ of FIG.1A.

Referring to FIGS. 1A and 1B, the light emitting element LD may includea first semiconductor layer SCL1, an active layer ACT, and a secondsemiconductor layer SCL2, which may be sequentially disposed along oneor a direction, and an insulating film INF surrounding an outercircumferential surface (for example, a side surface) of the firstsemiconductor layer SCL1, the active layer ACT, and the secondsemiconductor layer SCL2. For example, the light emitting element LD mayselectively further include an electrode layer ETL disposed on thesecond semiconductor layer SCL2. In this case, the insulating film INFmay or may not at least partially surround the outer circumferentialsurface of the electrode layer ETL.

In an embodiment, the light emitting element LD may be provided in astick (or rod) shape extending along one or a direction, and may have afirst end portion EP1 and a second end portion EP2 at both end portionsof a length L direction (or a thickness direction). The first endportion EP1 may be a first bottom surface (or an upper surface) of thelight emitting element LD, and the second end portion EP2 may be asecond bottom surface (or a lower surface) of the light emitting elementLD.

In describing an embodiment, the term “rod-shaped” may encompass arod-like shape or a bar-like shape that may be long (for example, havingan aspect ratio greater than about 1) in the length L direction, such asa substantially circular column or a substantially polygonal column, anda shape of a cross section thereof is not particularly limited. Forexample, a length L of the light emitting element LD may be greater thana diameter D (or a width of the cross section) thereof.

The first semiconductor layer SCL1, the active layer ACT, the secondsemiconductor layer SCL2, and the electrode layer ETL may besequentially disposed in a direction from the second end portion EP2 tothe first end portion EP1 of the light emitting element LD. For example,the first semiconductor layer SCL1 may be disposed on the second endportion EP2 of the light emitting element LD, and the electrode layerETL may be disposed on the first end portion EP1 of the light emittingelement LD.

The first semiconductor layer SCL1 may be a semiconductor layer of afirst conductivity type. For example, the first semiconductor layer SCL1may be an N-type semiconductor layer including an N-type dopant. Forexample, the first semiconductor layer SCL1 may include any onesemiconductor material among InAlGaN, GaN, AlGaN, InGaN, AlN, and InN,and may be an N-type semiconductor layer doped with a dopant such as Si,Ge, or Sn. However, the material forming the first semiconductor layerSCL1 is not limited thereto, and various materials in addition to theabove-described materials may form the first semiconductor layer SCL1.

The active layer ACT may be disposed on the first semiconductor layerSCL1 and may be formed in a single-quantum well or multi-quantum wellstructure. A position of the active layer ACT may be variously changedaccording to the type of the light emitting element LD. The active layerACT may emit light having a wavelength in a range of about 400 nm toabout 900 nm, and may use a double hetero-structure.

A clad layer (not shown) doped with a conductive dopant may beselectively formed on and/or under or below the active layer ACT. Forexample, the clad layer may be formed of an AlGaN layer or an InAlGaNlayer. According to an embodiment, a material such as AlGaN or AlInGaNmay be used to form the active layer ACT, and various materials inaddition to the above-described materials may form the active layer ACT.

In a case that a voltage equal to or greater than a threshold voltagemay be applied to the both end portions of the light emitting elementLD, the light emitting element LD may emit light while electron-holepairs may be combined in the active layer ACT. By controlling lightemission of the light emitting element LD using such a principle, thelight emitting element LD may be used as a light source of various lightemitting devices including a pixel of a display device.

The second semiconductor layer SCL2 may be disposed on the active layerACT and may be a semiconductor layer of a second conductive typedifferent from that of the first semiconductor layer SCL1. For example,the second semiconductor layer SCL2 may include a P-type semiconductorlayer including a P-type dopant. For example, the second semiconductorlayer SCL2 may include at least one semiconductor material amongInAlGaN, GaN, AlGaN, InGaN, AlN, and InN, and may be a P-typesemiconductor layer doped with a dopant such as Mg. However, thematerial forming the second semiconductor layer SCL2 is not limitedthereto, and various materials in addition to the above-describedmaterials may form the second semiconductor layer SCL2.

In an embodiment, the first semiconductor layer SCL1 and the secondsemiconductor layer SCL2 may have different lengths (or thicknesses) inthe length L direction of the light emitting element LD. For example,the first semiconductor layer SCL1 may have a length (or a thickness)longer (or thicker) than that of the second semiconductor layer SCL2along the length L direction of the light emitting element LD.Accordingly, the active layer ACT of the light emitting element LD maybe positioned closer to the first end portion EP1 than the second endportion EP2.

The electrode layer ETL may be disposed on the second semiconductorlayer SCL2. The electrode layer ETL may protect the second semiconductorlayer SCL2, and may be a contact electrode for smoothly electricallyconnecting the second semiconductor layer SCL2 to a predeterminedelectrode, line, or the like within the spirit and the scope of thedisclosure.

For example, the electrode layer ETL may be an ohmic contact electrodeor a Schottky contact electrode.

The electrode layer ETL may be substantially transparent or translucent.Accordingly, light generated by the light emitting element LD may betransmitted to the outside of the light emitting element LD through theelectrode layer ETL. In an embodiment, in a case that the lightgenerated by the light emitting element LD does not pass through theelectrode layer ETL and emitted to the outside of the light emittingelement LD through an area except for one end portion of the lightemitting element LD in which the electrode layer ETL is disposed, theelectrode layer ETL may be formed to be opaque.

In an embodiment, the electrode layer ETL may include metal or metaloxide. For example, the electrode layer ETL may be formed using chromium(Cr), titanium (Ti), aluminum (Al), gold (Au), nickel (Ni), ITO, IZO,ITZO, oxide or alloy thereof, and the like alone or in combination.

The insulating film INF may expose the electrode layer ETL and the firstsemiconductor layer SCL1 at the first and second end portions EP1 andEP2 of the light emitting element LD, respectively.

In a case that the insulating film INF is provided to cover or overlap asurface of the light emitting element LD, for example, the outercircumferential surface of the first semiconductor layer SCL1, theactive layer ACT, the second semiconductor layer SCL2, and/or theelectrode layer ETL, a short defect through the light emitting elementLD may be prevented. Accordingly, electrical stability of the lightemitting element LD may be secured.

In a case that the insulating film INF is provided on the surface of thelight emitting element LD, a surface defect of the light emittingelement LD may be minimized, and thus life and efficiency may beimproved. For example, in a case that the insulating film INF may beformed or disposed on each light emitting element LD, even though aplurality of light emitting elements LD may be disposed close to eachother, occurrence of an unwanted short circuit between the lightemitting elements LD may be prevented.

In an embodiment, the light emitting element LD may be manufacturedthrough a surface treatment process. For example, the surface treatmentmay be performed on each light emitting element LD so that in a casethat a plurality of light emitting elements LD may be mixed in a fluidsolution (or solvent) and supplied to each light emitting area (forexample, a light emitting area of each pixel), the light emittingelements LD may be uniformly dispersed in the solution without beingun-uniformly aggregated. As a non-limiting embodiment related to this,the insulating film INF itself may be formed as a hydrophobic film usinga hydrophobic material, or a hydrophobic film formed of a hydrophobicmaterial may be additionally formed or disposed on the insulating filmINF.

The insulating film INF may include a transparent insulating material.Accordingly, light generated in the active layer ACT may pass throughthe insulating film INF and be emitted to the outside of the lightemitting element LD. For example, the insulating film INF may include atleast one insulating material of SiO2 or silicon oxide (SiOx) but is notconfined thereto, Si₃N₄ or silicon nitride (SiNx) but is not confinedthereto, Al₂O₃ or aluminum oxide (Al_(x)O_(y)) but is not confinedthereto, and TiO₂ or titanium oxide (Ti_(x)O_(y)) but is not confinedthereto, but is not limited thereto.

In an embodiment, the light emitting element LD may have a size as smallas nano scale to micro scale. For example, each light emitting elementLD may have the diameter D (or width) and/or the length L of a nanoscale to micro scale range. However, a size of the light emittingelement LD is not limited thereto in the disclosure. For example, thesize of the light emitting element LD may be variously changed accordingto a design condition of various light emitting devices using the lightemitting element LD as a light source.

A light emitting device including the light emitting element LD may beused in various types of devices that require a light source, includinga display device. For example, a plurality of light emitting elements LDmay be arranged or disposed in each pixel of a display panel, and thelight emitting elements LD may be used as a light source of each pixel.However, an application field of the light emitting element LD is notlimited to the above-described example, and the light emitting elementLD may be used in other types of devices such as a lighting device.

FIG. 2 is a plan view illustrating a display device according to anembodiment. FIG. 2 shows a display device, for example, a display panelPNL included in the display device, as an example of an electronicdevice that may use the light emitting element LD described in anembodiment of FIGS. 1A and 1B as a light source. For example, each pixelunit PXU of the display panel PNL and each pixel forming the pixel unitPXL may include at least one light emitting element LD.

For convenience, in FIG. 2, a structure of the display panel PNL may beshown centering on a display area DA. However, according to anembodiment, at least one driving circuit unit, lines and/or pads, whichare not shown, may be further disposed on the display panel PNL.

Referring to FIG. 2, the display panel PNL according to an embodimentmay include a base layer BSL and pixels disposed on the base layer BSL.The pixels may include first color pixels CPX1, second color pixelsCPX2, and/or third color pixels CPX3. Hereinafter, in a case that one ormore pixels of the first color pixels CPX1, the second color pixelsCPX2, and the third color pixels CPX3 may be arbitrarily referred to, orin a case that two or more types of pixels may be collectively referredto, the one or more pixels or two or more types of pixels may bereferred to as a “pixel PXL” or “pixels PXL”.

By way of example, the display panel PNL and the base layer BSL forforming the display panel PNL may include the display area DA fordisplaying an image, and a non-display area NDA excluding the displayarea DA. For example, the pixels PXL may be disposed in the display areaDA on the base layer BSL.

The display area DA may be disposed in a center area of the displaypanel PNL, and the non-display area NDA may be disposed in an edge areaof the display panel PNL to surround or to be adjacent to the displayarea DA. However, positions of the display area DA and the non-displayarea NDA may be changed.

The base layer BSL may form a base member of the display panel PNL, andmay be a rigid or flexible substrate or film. For example, the baselayer BSL may be a rigid substrate formed of glass or tempered glass, aflexible substrate (or a thin film) of a material of plastic or metal,or at least one insulating film. The material and/or physical propertiesof the base layer BSL are/is not particularly limited.

One area on the base layer BSL may be defined as the display area DA andthe pixels PXL may be disposed, and the remaining areas may be definedas the non-display area NDA. For example, the base layer BSL may includethe display area DA including a plurality of pixel areas in which eachpixel PXL may be formed or disposed, and the non-display area NDAdisposed outside the display area DA. Various lines, pads, and/orbuilt-in circuit units electrically connected to the pixels PXL of thedisplay area DA may be disposed in the non-display area NDA.

The pixels PXL may be arranged or disposed in the display area DA. Forexample, the pixels PXL may be regularly arranged or disposed in thedisplay area DA along a first direction DR1 and a second direction DR2according to a stripe or pen-tile arrangement structure, and the likewithin the spirit and the scope of the disclosure. However, anarrangement structure of the pixels PXL is not limited thereto, and thepixels PXL may be arranged or disposed in the display area DA in variousstructures and/or methods.

According to an embodiment, two or more types of pixels PXL emittinglight of different colors may be disposed in the display area DA. Forexample, in the display area DA, the first color pixels CPX1 (or firstsub pixels) that emit light of a first color, the second color pixelsCPX2 (or second sub pixels) that emit light of a second color, and thirdcolor pixels CPX3 (or third sub pixels) that emit light of a third colormay be arranged or disposed. For example, the first color pixel CPX1,the second color pixel CPX2, and the third color pixel CPX3 disposed tobe adjacent to each other may form one pixel unit PXU capable ofemitting light of various colors.

According to an embodiment, the first color pixel CPX1 may be a redpixel that emits red light, the second color pixel CPX2 may be a greenpixel that emits green light, and the third color pixel CPX3 may be ablue pixel that emits blue light. In an embodiment, the first colorpixel CPX1, the second color pixel CPX2, and the third color pixel CPX3may include a first color light emitting element, a second color lightemitting element, and a third color light emitting element as a lightsource, to emit light of the first color, the second color, and thethird color, respectively. In an embodiment, the first color pixel CPX1,the second color pixel CPX2, and the third color pixel CPX3 may includelight emitting elements of the same color, and may emit light of thefirst color, the second color, and the third color, respectively, byincluding a color conversion layer and/or a color filter of differentcolors disposed on the respective light emitting elements, respectively.

However, the color, type, number, and/or the like of the pixels PXLforming each pixel unit PXU are/is not particularly limited. Forexample, the color of light emitted by each pixel PXL may be variouslychanged.

The pixel PXL may include at least one light source driven by apredetermined control signal (for example, a scan signal and a datasignal) and/or predetermined power (for example, first power and secondpower). In an embodiment, the light source may include at least onelight emitting element LD according to an embodiment of FIGS. 1A and 1B,for example, at least one rod-shaped light emitting element LD having asize as small as nano scale to micro scale, but the disclosure is notlimited thereto. For example, in an embodiment, the light source of eachpixel PXL may be formed using a light emitting element LD of acore-shell structure.

For example, the pixel PXL may have a structure according to at leastone of embodiments described below. For example, each pixel PXL may havea structure according to any one of the embodiments disclosed in FIGS. 3to 5B, or may have a structure in which at least two embodiments of theabove-described embodiments may be combined.

In an embodiment, the pixel PXL may be formed as an active pixel, but isnot limited thereto. For example, the pixel PXL may be formed as a pixelof a passive or active light emitting display device of variousstructures and/or driving methods.

FIG. 3 is an equivalent circuit diagram illustrating the pixel PXL ofthe display device according to an embodiment. For example, FIG. 3illustrates an embodiment of the pixel PXL that may be applied to anactive display device. However, types of the pixel PXL and the displaydevice to which an embodiment may be applied are not limited thereto.

According to an embodiment, each pixel PXL shown in FIG. 3 may be anyone of the first color pixel CPX1, the second color pixel CPX2, and thethird color pixel CPX3 included in the display panel PNL of FIG. 2. Forexample, the first color pixel CPX1, the second color pixel CPX2, andthe third color pixel CPX3 may have structures substantially the same asor similar to each other.

Referring to FIG. 3, the pixel PXL may include a light emitting unit EMUfor generating light of a luminance corresponding to a data signal. Forexample, the pixel PXL may further include a pixel circuit PXC fordriving the light emitting unit EMU.

The light emitting unit EMU may include at least one light emittingelement LD, for example, a plurality of light emitting elements LD,electrically connected between first power VDD and second power VSS. Indescribing each embodiment, a term “connection (or access)” maycomprehensively mean a physical and/or electrical connection (oraccess). For example, this may comprehensively mean a direct or indirectconnection (or access) and an integral or non-integral connection (oraccess).

For example, the light emitting unit EMU may include a first electrodeELT1 (also referred to as a “first pixel electrode” or a “firstalignment electrode”) electrically connected to the first power VDD viathe pixel circuit PXC and a first power line PL1, a second electrodeELT2 (also referred to as a “second pixel electrode” or a “secondalignment electrode”) electrically connected to the second power VSS viaa second power line PL2, and the plurality of light emitting elements LDelectrically connected in parallel in the same direction between thefirst and second electrodes ELT1 and ELT2. In an embodiment, the firstelectrode ELT1 may be an anode electrode, and the second electrode ELT2may be a cathode electrode.

Each of the light emitting elements LD may include the first end portionEP1 (for example, a P-type end portion) electrically connected to thefirst power VDD through the first electrode ELT1 and/or the pixelcircuit PXC, and the second end portion EP2 (for example, an N-type endportion) electrically connected to the second power VSS through thesecond electrode ELT2. For example, the light emitting elements LD maybe electrically connected in parallel in a forward direction between thefirst and second electrodes ELT1 and ELT2. Each light emitting elementLD electrically connected in the forward direction between the firstpower VDD and the second power VSS may form each effective light source,and the effective light sources may be gathered to form the lightemitting unit EMU of the pixel PXL.

The first power VDD and the second power VSS may have differentpotentials so that the light emitting elements LD emit light. Forexample, the first power VDD may be set as a high potential power, andthe second power VSS may be set as a low potential power.

The first end portion EP1 of the light emitting elements LD forming eachlight emitting unit EMU may be commonly electrically connected to thepixel circuit PXC through one electrode (for example, the firstelectrode ELT1 of each pixel PXL) of the light emitting unit EMU, andmay be electrically connected to the first power VDD through the pixelcircuit PXC and the first power line PL1. For example, the second endportion EP2 of the light emitting elements LD may be commonlyelectrically connected to the second power VSS through another electrode(for example, the second electrode ELT2 of each pixel PXL) of the lightemitting unit EMU and the second power line PL2.

The light emitting elements LD may emit light at a luminancecorresponding to a driving current supplied through a correspondingpixel circuit PXC. For example, during each frame period, the pixelcircuit PXC may supply a driving current corresponding to a grayscalevalue to be expressed in a corresponding frame to the light emittingunit EMU. The driving current supplied to the light emitting unit EMUmay be divided and flow to the light emitting elements LD electricallyconnected in the forward direction. Accordingly, while each lightemitting element LD emits light at a luminance corresponding to thecurrent flowing therein, the light emitting unit EMU may emit light of aluminance corresponding to the driving current.

In an embodiment, the light source unit LSU may further include at leastone ineffective light source in addition to the light emitting elementsLD forming each effective light source. For example, at least oneineffective light emitting element which may be arranged or disposed ina reverse direction or of which at least one or an end portion may befloated may be further electrically connected to at least one seriesstage. The ineffective light emitting element maintains a deactivatedstate even though a driving voltage (for example, a driving voltage of aforward direction) may be applied between the first and secondelectrodes ELT and ELT2, and thus a non-light emitting state may besubstantially maintained.

Meanwhile, although FIG. 3 discloses an embodiment in which the pixelPXL may include the light emitting unit EMU of a parallel structure, thedisclosure is not limited thereto. For example, the pixel PXL mayinclude a light emitting unit EMU of a series structure or aseries/parallel structure. In this case, the light emitting unit EMU mayinclude the light emitting elements LD electrically connected in theseries structure or the series/parallel structure between the firstelectrode ELT1 and the second electrode ELT2.

The pixel circuit PXC may be electrically connected between the firstpower VDD and the first electrode ELT1. The pixel circuit PXC may beelectrically connected to a scan line SL and a data line DL of thecorresponding pixel PXL. For example, the pixel circuit PXC may beselectively electrically connected to a sensing signal line SSL and asensing line SENL.

The pixel circuit PXC may include a first transistor M1, a secondtransistor M2, a third transistor M3, and a storage capacitor Cst.

The first transistor M1 may be electrically connected between the firstpower VDD and the first electrode ELT1 of the light emitting unit EMU.For example, a gate electrode of the first transistor M1 may beelectrically connected to a first node N1. The first transistor M1controls the driving current supplied to the light emitting unit incorrespondence with a voltage of the first node N1. For example, thefirst transistor M1 may be a driving transistor that controls a drivingcurrent of the pixel PXL.

For example, the first transistor M1 may further include a back gateelectrode electrically connected to the first electrode ELT1. The backgate electrode may be disposed to overlap the gate electrode with aninsulating layer interposed therebetween.

The second transistor M2 may be electrically connected between the dataline DL and the first node N1. For example, a gate electrode of thesecond transistor M2 may be electrically connected to the scan line SL.The second transistor M2 is turned on in a case that a scan signal of agate-on voltage (for example, a high level voltage) is supplied from thescan line SL, to electrically connect the data line DL and the firstnode N1.

For each frame period, a data signal of a corresponding frame issupplied to the data line DL, and the data signal is transferred to thefirst node N1 through the turned on second transistor M2 during a periodin which the scan signal of the gate-on voltage is supplied. Forexample, the second transistor M2 may be a switching transistor fortransferring each data signal to the inside of the pixel PXL.

One electrode of the storage capacitor Cst may be electrically connectedto the first node N1, and another electrode may be electricallyconnected to a second electrode of the transistor M1. The storagecapacitor Cst charges a voltage corresponding to the data signalsupplied to the first node N1 during each frame period.

The third transistor M3 may be electrically connected between the firstelectrode ELT1 of the light emitting unit EMU (or the second electrodeof the first transistor M1) and the sensing line SENL. For example, agate electrode of the third transistor M3 may be electrically connectedto the sensing signal line SSL. The third transistor M3 may transfers avoltage value applied to the first electrode ELT1 of the light emittingunit EMU to the sensing line SENL according to a sensing signal suppliedto the sensing signal line SSL during a predetermined sensing period.The voltage value transferred through the sensing line SENL may beprovided to an external circuit (for example, a timing controller), andthe external circuit may extract characteristic information (forexample, a threshold voltage or the like of the first transistor M1) ofeach pixel PXL based on the provided voltage value. The extractedcharacteristic information may be used to convert image data so that acharacteristic deviation between the pixels PXL is compensated.

Meanwhile, in FIG. 3, all transistors included in the pixel circuit PXC,for example, the first, second, and third transistors M1, M2, and M3 maybe N-type transistors, but the disclosure is not limited thereto. Forexample, at least one of the first, second, and third transistors M1,M2, and M3 may be changed to a P-type transistor. In an embodiment, thepixel circuit PXC may include P-type and N-type transistors incombination.

For example, a structure and a driving method of the pixel PXL may bevariously changed. For example, the pixel circuit PXC may be formed of apixel circuit of various structures and/or driving methods, in additionto an embodiment shown in FIG. 3.

For example, the pixel circuit PXC may not include the third transistorM3. For example, the pixel circuit PXC may further include other circuitelements such as a compensation transistor for compensating for thethreshold voltage of the first transistor M1, an initializationtransistor for initializing the voltage of the first node N1 or thefirst electrode ELT1 of the light emitting unit EMU, a light emittingcontrol transistor for controlling a period in which the driving currentis supplied to the light emitting unit EMU, and/or a boosting capacitorfor boosting the voltage of the first node N1.

In an embodiment, in a case that each pixel PXL may be formed in apassive light emitting display device or the like, the pixel circuit PXCmay be omitted. For example, each of the first and second electrodesELT1 and ELT2 of the light emitting unit EMU may be directlyelectrically connected to the scan line SL, the data line DL, the firstpower line PL1, the second power line PL2, other signal lines or powerlines, or the like within the spirit and the scope of the disclosure.

FIGS. 4A and 4B are plan views illustrating the pixel PXL of the displaydevice according to an embodiment, respectively. In FIGS. 4A and 4B, astructure of the pixel PXL is shown centering on the light emitting unitEMU of the pixel PXL. For example, FIGS. 4A and 4B illustrate an examplestructure of the light emitting unit EMU including the first and secondelectrodes ELT1 and ELT2, and the plurality of light emitting elementsLD electrically connected in parallel between the first and secondelectrodes ELT1 and ELT2, as in an embodiment of FIG. 3. However, thestructure of the light emitting unit EMU, including a connectionstructure of the light emitting elements LD, may be variously changed.

For example, FIGS. 4A and 4B show an embodiment in which each lightemitting unit EMU may be electrically connected to a predetermined powerline (for example, the first and/or second power line PL1 and/or PL2)through first and second contact holes CH1 and CH2, a circuit element(for example, at least one circuit element forming the pixel circuitPXC) and/or the signal line (for example, the scan line SL and/or thedata line DL). However, in an embodiment, at least one of the first andsecond electrodes ELT1 and ELT2 of each pixel PXL may be directlyelectrically connected to the predetermined power line and/or the signalline without passing through a contact hole, an intermediate line,and/or the like within the spirit and the scope of the disclosure.

First, referring to FIG. 4A, the pixel PXL may include the firstelectrode ELT1 and the second electrode ELT2 disposed in each lightemitting area EMA, and at least one light emitting element LD (forexample, a plurality of light emitting elements LD electricallyconnected in parallel between the first and second electrodes ELT1 andELT2) disposed between the first electrode ELT1 and the second electrodeELT2. Here, the term “the light emitting element LD is disposed betweenthe first and second electrodes ELT1 and ELT2” may mean that at leastone region of the light emitting element LD is positioned between aregion between the first and second electrodes ELT1 and ELT2 on the planview.

For example, the pixel PXL may further include a first contact electrodeCNE1 and a second contact electrode CNE2 that electrically connect thelight emitting elements LD to the region between the first and secondelectrodes ELT1 and ELT2.

The first electrode ELT1 and the second electrode ELT2 may be disposedin each pixel area in which each pixel PXL may be provided or disposedand/or formed. For example, the first electrode ELT1 and the secondelectrode ELT2 may be disposed in the light emitting area EMA of eachpixel PXL.

According to an embodiment, each pixel area may comprehensively mean apixel circuit area in which circuit elements for forming a correspondingpixel PXL may be disposed and the light emitting area EMA in which thelight emitting unit EMU of the pixel PXL is disposed. For example, thelight emitting area EMA may be an area in which the light emittingelements LD (for example, the effective light sources electricallyconnected in the forward direction between the first and secondelectrodes ELT1 and ELT2) forming the light emitting unit EMU of eachpixel PXL may be disposed. For example, in the light emitting area EMA,predetermined electrodes (for example, the first and second electrodesELT1 and ELT2, and/or the first and second contact electrodes CNE1 andCNE2) electrically connected to the light emitting elements LD, or oneregion of the electrodes may be disposed.

The light emitting area EMA may be surrounded by a light-blocking and/orreflective bank structure (for example, a pixel defining film and/or ablack matrix) formed or disposed between the pixels PXL to define eachpixel area and the light emitting area EMA therein. For example, a bankstructure (corresponding to a “second bank BNK2” of FIG. 4B) surroundingthe light emitting area EMA may be disposed around the light emittingarea EMA.

The first and second electrodes ELT1 and ELT2 may be disposed to bespaced apart from each other. For example, each of the first and secondelectrodes ELT1 and ELT2 may extend along the first direction DR1 in thelight emitting area EMA, and the first and second electrodes ELT1 andELT2 may be spaced apart along the second direction DR2 crossing orintersecting the first direction DR1 by a predetermined interval. In anembodiment, the first direction DR1 may be a vertical direction (or acolumn direction), and the second direction DR2 may be a horizontaldirection (or a row direction), but the disclosure is not limitedthereto.

According to an embodiment, the first and/or second electrodes ELT1 andELT2 may have a pattern separated for each pixel PXL or a patterncommonly connected in a plurality of pixels PXL. For example, as shownin FIG. 4A, the first and second electrodes ELT1 and ELT2 may have anindependent pattern of which both ends may be cut outside acorresponding light emitting area EMA or inside the light emitting areaEMA. In an embodiment, the first electrode ELT1 may have an independentpattern for example cut outside a corresponding light emitting area EMAor inside the light emitting area EMA, and one end portion of the secondelectrode ELT2 may extend along the first direction DR1 or a seconddirection DR2 and thus the second electrode ELT2 may be integrallyconnected to the second electrode ELT2 of another pixel PXL adjacent inthe first direction DR1 or the second direction DR2.

Meanwhile, before a process of forming the pixel PXL, for example, analignment of the light emitting elements LD may be completed, the firstelectrodes ELT1 of the pixels PXL disposed in the display area DA may beelectrically connected to each other, and the second electrodes ELT2 ofthe pixels PXL may be electrically connected to each other. For example,before the alignment of the light emitting elements LD is completed, thefirst electrodes ELT1 of the pixels PXL may be integrally ornon-integrally formed and electrically connected to each other, and thesecond electrodes ELT2 of the pixels PXL may be integrally ornon-integrally formed and electrically connected to each other. In acase that the first electrodes ELT1 or the second electrodes ELT2 of thepixels PXL may be non-integrally connected to each other, the firstelectrodes ELT1 or the second electrodes ELT2 may be electricallyconnected to each other at least one contact hole, a bridge pattern,and/or the like within the spirit and the scope of the disclosure.

The first and second electrodes ELT1 and ELT2 (or first and secondalignment lines before separation into the respective first and secondelectrodes ELT1 and ELT2) may receive a first alignment signal (or afirst alignment voltage) and a second alignment signal (or a secondalignment voltage) in aligning the light emitting elements LD,respectively. For example, one of the first and second electrodes ELT1and ELT2 may receive an alignment signal of an alternating current type,and the other of the first and second electrodes ELT1 and ELT2 mayreceive an alignment voltage (for example, a ground voltage) having aconstant voltage level.

For example, a predetermined alignment signal may be applied to thefirst and second electrodes ELT1 and ELT2 in aligning the light emittingelements LD. Accordingly, an electric field may be formed between thefirst and second electrodes ELT1 and ELT2. The light emitting elementsLD supplied to each pixel area (for example, the light emitting area EMAof each pixel PXL) may be self-aligned between the first and secondelectrodes ELT1 and ELT2 by the electric field. For example, the lightemitting elements LD may be aligned between the first and secondelectrodes ELT1 and ELT2 so that the first end portion EP1 and thesecond end portion EP2 may be adjacent to the first electrode ELT1 andthe second electrode ELT2, respectively. After the alignment of thelight emitting elements LD is completed, the pixels PXL may beindividually driven by disconnecting at least the first electrodes ELT1between the pixels PXL.

The first and second electrodes ELT1 and ELT2 may have various shapes.For example, each of the first and second electrodes ELT1 and ELT2 mayhave a substantially bar shape extending in one or a direction. Forexample, each of the first and second electrodes ELT1 and ELT2 may havea substantially bar shape extending along the first direction DR1. In anembodiment, the first and second electrodes ELT1 and ELT2 may have asubstantially bent or substantially curved shape in at least one region.For example, each of the first and second electrodes ELT1 and ELT2 mayhave a uniform width or different widths for each region.

For example, the shape and/or structure of the first and secondelectrodes ELT1 and ELT2 may be variously changed. For example, thefirst electrode ELT1 and/or the second electrode ELT2 may be formed as asubstantially spiral or substantially circular electrode.

For example, FIG. 4A discloses an embodiment in which one firstelectrode ELT1 and one second electrode ELT2 may be disposed in eachlight emitting area EMA, but the number and/or a mutual dispositionstructure of the first and second electrodes ELT1 and ELT2 disposed ineach pixel PXL may be variously changed.

In a case that a plurality of first electrodes ELT1 may be disposed inone pixel PXL, the first electrodes ELT1 may be integrally ornon-integrally connected to each other. For example, the firstelectrodes ELT1 may be integrally connected or may be connected to eachother by a bridge pattern positioned on a layer (for example, a circuitlayer on which the pixel circuit PXC is disposed) different from that ofthe first electrodes ELT1. Similarly, in a case that a plurality ofsecond electrodes ELT2 may be disposed in one pixel PXL, the secondelectrodes ELT2 may be integrally or non-integrally connected to eachother.

For example, in the disclosure, the shape, number, arrangementdirection, mutual disposition relationship, and/or the like of the firstand second electrodes ELT1 and ELT2 disposed in each pixel PXL may bevariously changed.

In an embodiment, the first electrode ELT1 may be electrically connectedto a predetermined circuit element (for example, at least one transistorforming the pixel circuit PXC), a power line (for example, the firstpower line PL1), and/or the signal line (for example, the scan line SL,the data line DL, or a predetermined control line) through a firstcontact hole CH1. In an embodiment, the first electrode ELT1 may bedirectly electrically connected to a predetermined power line or signalline.

In an embodiment, the first electrode ELT1 may be electrically connectedto a predetermined circuit element disposed under or below the firstelectrode ELT1 through the first contact hole CH1 and may beelectrically connected to a first line through the circuit element. Thefirst line may be the first power line PL1 for supplying the first powerVDD, but is not limited thereto.

In an embodiment, the second electrode ELT2 may be electricallyconnected to a predetermined circuit element (for example, at least onetransistor forming the pixel circuit PXC), a power line (for example,the second power line PL2), and/or a signal line (for example, the scanline SL, the data line DL, or a predetermined control line) through thesecond contact hole CH2. In an embodiment, the second electrode ELT2 maybe directly electrically connected to a predetermined power line orsignal line.

In an embodiment, the second electrode ELT2 may be electricallyconnected to a second line disposed under or below the second electrodeELT2 through a second contact hole CH2. The second line may be thesecond power line PL2 for supplying the second power VSS, but is notlimited thereto.

Each of the first and second electrodes ELT1 and ELT2 may be formed of asingle layer or multiple layers. For example, the first electrode ELT1may include a reflective electrode layer of at least one layer includinga reflective conductive material, and may selectively further include atransparent electrode layer and/or a conductive capping layer of atleast one layer. Similarly, the second electrode ELT2 may include areflective electrode layer of at least one layer including a reflectiveconductive material, and may selectively further include a transparentelectrode layer and/or a conductive capping layer of at least one layer.The reflective conductive material may be at least one of various metalmaterials including a metal having high reflectance in a visible lightwavelength band, for example, aluminum (Al), gold (Au), and silver (Ag),but is not limited thereto.

The light emitting elements LD may be disposed between the firstelectrode ELT1 and the second electrode ELT2. For example, the lightemitting elements LD may be arranged or disposed and electricallyconnected in parallel between the first electrode ELT1 and the secondelectrode ELT2. For example, each light emitting element LD may bealigned in the second direction DR2 between the first electrode ELT1 andthe second electrode ELT2, and may be electrically connected between thefirst and second electrodes ELT1 and ELT2.

Meanwhile, FIG. 4A shows that all light emitting elements LD may beuniformly aligned in the second direction DR2, but the disclosure is notlimited thereto. For example, at least one of the light emittingelements LD may be aligned in a diagonal direction or the like inclinedwith respect to the first and second directions DR1 and DR2 between thefirst and second electrodes ELT1 and ELT2.

According to an embodiment, each light emitting element LD may be amicro light emitting element of a small size as small as, for example, anano scale to a micro scale, using a material of an inorganic crystalstructure, but is not limited thereto. For example, each light emittingelement LD may be the rod-shaped light emitting element LD as shown inFIGS. 1A and 1B, but is not limited thereto.

Each light emitting element LD may include the first end portion EP1disposed toward the first electrode ELT1, and the second end portion EP2disposed toward the second electrode ELT2. In an embodiment, each lightemitting element LD may overlap the first electrode ELT1 and/or thesecond electrode ELT2, or may not overlap the first electrode ELT1and/or the second electrode ELT2.

The first end portion EP1 of each of the light emitting elements LD maybe electrically connected to the first electrode ELT1, and the secondend portion EP2 of each of the light emitting elements LD may beelectrically connected to the second electrode ELT2. For example, thefirst end portion EP1 of each of the light emitting elements LD may beelectrically connected to the first electrode ELT1 through the firstcontact electrode CNE1, and the second end portion EP2 of each of thelight emitting elements LD may be electrically connected to the secondelectrode ELT2 through the second contact electrode CNE2. In anembodiment, the first end portion EP1 of each of the light emittingelements LD may be electrically connected to the first electrode ELT1 bydirectly contacting the first electrode ELT1. Similarly, the second endportion EP2 of each of the light emitting elements LD may beelectrically connected to the second electrode ELT2 by directlycontacting the second electrode ELT2. In this case, the first contactelectrode CNE1 and/or the second contact electrode CNE2 may beselectively formed.

The light emitting elements LD may be prepared in a form dispersed in apredetermined solution, and may be supplied to each pixel area (forexample, the light emitting area EMA of each pixel PXL) through variousmethods including an inkjet method or a slit coating method. Forexample, the light emitting elements LD may be mixed with a volatilesolvent and supplied to the light emitting area EMA of each pixel PXL.At this time, in a case that a predetermined alignment voltage (or analignment signal) may be applied to the first and second electrodes ELT1and ELT2 of the pixels PXL, an electric field may be formed between thefirst and second electrodes ELT1 and ELT2, and thus the light emittingelements LD may be aligned between the first and second electrodes ELT1and ELT2. After the light emitting elements LD are aligned, the lightemitting elements LD may be stably arranged or disposed between thefirst and second electrodes ELT1 and ELT2 by volatilizing the solvent orremoving the solvent in or by other methods.

The first contact electrode CNE1 and the second contact electrode CNE2may be formed or disposed on the both end portions of the light emittingelements LD, for example, the first and second end portions EP1 and EP2,respectively. Accordingly, the light emitting elements LD may be stablyconnected between the first and second electrodes ELT1 and ELT2.

The first contact electrode CNE1 may be disposed on the first electrodeELT1 and the first end portion EP1 of the light emitting element LD soas to overlap the first electrode ELT1 and the first end portion EP1 ofat least one light emitting element LD adjacent to the first electrodeELT1. For example, the first contact electrode CNE1 may be disposed onthe first electrode ELT1 and the first end portions EP1 of the lightemitting elements LD so as to overlap the first electrode ELT1 and thefirst end portions EP1 of the plurality of light emitting elements LDadjacent to the first electrode ELT1.

The first contact electrode CNE1 may electrically connect the firstelectrode ELT1 and the first end portions EP1 of the light emittingelements LD. For example, the first contact electrode CNE1 may stablyfix the first end portions EP1 of the light emitting elements LD.

The second contact electrode CNE2 may be disposed on the secondelectrode ELT2 and the second end portion EP2 of the light emittingelement LD so as to overlap the second electrode ELT2 and the second endportion EP2 of at least one light emitting element LD adjacent to thesecond electrode ELT2. For example, the second contact electrode CNE2may be disposed on the second electrode ELT2 and the second end portionsEP2 of the light emitting elements LD so as to overlap the secondelectrode ELT2 and the second end portions EP2 of the plurality of lightemitting elements LD adjacent to the second electrode ELT2.

The second contact electrode CNE2 may electrically connect the secondelectrode ELT2 and the second end portions EP2 of the light emittingelements LD. For example, the second contact electrode CNE2 may stablyfix the second end portions EP2 of the light emitting elements LD.

Meanwhile, the pixel PXL may include a light emitting unit EMU of aseries or series/parallel structure including a plurality of lightemitting elements LD electrically connected to at least two seriesstages. In this case, the light emitting unit EMU may further include atleast one intermediate electrode electrically connected between thefirst and second electrodes ELT1 and ELT2 through the light emittingelements LD, and/or at least one contact electrode for electricallyconnecting the intermediate electrode to adjacent light emittingelements LD.

In the above-described embodiment, each light emitting element LDelectrically connected in the forward direction between the first andsecond electrodes ELT1 and ELT2 may form an effective light source ofthe corresponding pixel PXL. For example, such effective light sourcesmay be gathered to form the light emitting unit EMU of the correspondingpixel PXL.

Referring to FIG. 4B, the pixel PXL may further include a first bankBNK1 overlapping the first and second electrodes ELT1 and ELT2, and asecond bank BNK2 surrounding each light emitting area EMA.

The first bank BNK1 (also referred to as a “partition wall”) may bedisposed so as to overlap one region of the first and second electrodesELT1 and ELT2. For example, the first bank BNK1 may be disposed under orbelow the first and second electrodes ELT1 and ELT2 so as to overlap oneregion of each of the first and second electrodes ELT1 and ELT2 on theplan view.

The first bank BNK1 may be for forming a wall structure around the lightemitting elements LD, and may be formed in a separate or integralpattern. For example, the first bank BNK1 may include a (1-1)-th bankBNK1-1 and a (1-2)-th bank BNK1-2 separated from each other. The(1-1)-th bank BNK1-1 may overlap the first electrode ELT1 and the firstcontact electrode CNE1, and the (1-2)-th bank BNK1-2 may overlap thesecond electrode ELT2 and the second contact electrode CNE2. In anembodiment, the first bank BNK1 may be formed as an integral type bankof a shape surrounding a region in which the light emitting elements LDmay be disposed while having an opening or a groove corresponding to theregion in which the light emitting elements LD may be disposed.

In a case that the first bank BNK1 is disposed under or below one or aregion of each of the first and second electrodes ELT1 and ELT2, thefirst and second electrodes ELT1 and ELT2 may protrude in an upwarddirection in a region in which the first bank BNK1 may be formed ordisposed. The first bank BNK1 may form a reflective bank (also referredto as a “reflective partition wall”) together with the first and secondelectrodes ELT1 and ELT2. For example, the first and second electrodesELT1 and ELT2 and/or the first bank BNK1 may be formed of a reflectivematerial, or may form a reflective film on the first and secondelectrodes ELT1 and ELT2 and/or a protruded sidewall of the first bankBNK1.

Accordingly, light emitted from the first and second end portions EP1and EP2 of the light emitting elements LD facing the first and secondelectrodes ELT1 and ELT2 may be guided to be more directed to a frontdirection of the display panel PNL. Here, the front direction of thedisplay panel PNL may include a direction perpendicular to the displaypanel PNL (for example, an upper direction of the pixel PXL), and mayfurther comprehensively mean a direction belonging to a predeterminedviewing angle range. As described above, in a case that one region ofthe first and second electrodes ELT1 and ELT2 is protruded in the upwarddirection using the first bank BNK1, light efficiency of the pixel PXLmay be improved.

The second bank BNK2 may be a structure that defines the light emittingarea EMA of each pixel PXL, and may be, for example, a pixel definingfilm. For example, the second bank BNK2 may be disposed in a boundaryarea of each pixel area PXA in which the pixel PXL is provided and/or anarea between adjacent pixels PXL to surround the light emitting area EMAof each pixel PXL.

The second bank BNK2 may partially overlap the first and/or secondelectrodes ELT1 and ELT2 or may not overlap the first and/or secondelectrodes ELT1 and ELT2. For example, the first electrode ELT1 and/orthe second electrode ELT2 may extend to a non-light emitting area NEA soas to overlap the second bank BNK2, or may be disconnected within thelight emitting area EMA so as not to overlap the second bank BNK2.

For example, the second bank BNK2 may or may not overlap the firstcontact hole CH1 and/or the second contact hole CH2. For example, thefirst contact hole CH1 and/or the second contact hole CH2 may be formedin the non-light emitting area NEA so as to overlap the second bankBNK2, or may be formed in each light emitting area EMA so as not tooverlap the second bank BNK2.

The second bank BNK2 may be formed to include at least onelight-blocking and/or reflective material to prevent light leakagebetween adjacent pixels PXL. For example, the second bank BNK2 mayinclude at least one black matrix material (for example, at least onelight-blocking material) of various types of black matrix materials, acolor filter material of a specific or predetermined color, and/or thelike within the spirit and the scope of the disclosure. For example, thesecond bank BNK2 may be formed of a black opaque pattern to block lighttransmission.

For example, in supplying the light emitting elements LD to each pixelPXL, the second bank BNK2 may function as a dam structure defining eachlight emitting area EMA to which the light emitting elements LD is to besupplied. For example, each light emitting area EMA may be partitionedby the second bank BNK2, and thus a light emitting element ink of adesired type and/or amount may be supplied to the light emitting areaEMA.

In an embodiment, the second bank BNK2 may be simultaneously formed ordisposed on the same layer as the first banks BNK1 in a process offorming the first banks BNK1 of the pixels PXL. In an embodiment, thesecond bank BNK2 may be formed or disposed on a layer the same as ordifferent from that of the first banks BNK1 through a process separatefrom the process of forming the first banks BNK1.

FIGS. 5A and 5B are schematic cross-sectional views illustrating thepixel PXL of the display device according to an embodiment,respectively. For example, FIGS. 5A and 5B illustrate differentembodiments of a cross section of the pixel PXL along a line II˜II′ ofFIG. 4B. In comparison with FIG. 5A, an embodiment of FIG. 5B mayfurther include a second insulating layer INS2 disposed on the firstcontact electrode CNE1.

In FIGS. 5A and 5B, as an example of circuit elements that may bedisposed on the circuit layer PCL, an arbitrary transistor TR (forexample, a transistor electrically connected to the first electrode ELT1through the first contact hole CH1 and the bridge pattern BRP) is shown.For example, as an example of a line that may be disposed on the circuitlayer PCL, the second power line PL2 electrically connected to thesecond electrode ELT2 through the second contact hole CH2 is shown.

Referring to FIGS. 2 to 5B, the pixel PXL and the display deviceincluding the same according to an embodiment include the circuit layerPCL and the display layer DPL disposed to overlap each other on onesurface of the base layer BSL. For example, the display area DA mayinclude the circuit layer PCL sequentially disposed (stacked) in a thirddirection DR3 (for example, a height or thickness direction) on onesurface of the base layer BSL, and the display layer DPL disposed on thecircuit layer PCL. However, a mutual position of the circuit layer PCLand the display layer DPL on the base layer BSL may vary according to anembodiment.

The circuit elements (for example, the transistors TR and the storagecapacitors Cst) forming the pixel circuit PXC of the corresponding pixelPXL and various lines electrically connected to the circuit elements maybe disposed in each pixel area PXA of the circuit layer PCL. Forexample, the first and second electrodes ELT1 and ELT2, the lightemitting elements LD, and/or the first and second electrodes CNE1 andCNE2 forming the light emitting unit EMU of the corresponding pixel PXLmay be disposed in each pixel area PXA of the display layer DPL.

The circuit layer PCL may include a plurality of insulating layers inaddition to the circuit elements and the lines. For example, the circuitlayer PCL may include a buffer layer BFL, a gate insulating layer GI, afirst interlayer insulating layer ILD1, a second interlayer insulatinglayer ILD2, and/or a passivation layer PSV sequentially stacked on onesurface of the base layer BSL.

For example, the circuit layer PCL may selectively further include afirst conductive layer including at least one light blocking layer (or aback gate electrode BGE of the transistor TR) or the like disposed underor below at least a portion of the transistor TR.

The buffer layer BFL may be disposed on one surface of the base layerBSL including the first conductive layer. The buffer layer BFL mayprevent an impurity from diffusing into each circuit element.

A semiconductor layer may be disposed on the buffer layer BFL. Thesemiconductor layer may include a semiconductor pattern SCP of eachtransistor TR. The semiconductor pattern SCP may include a channelregion overlapping a gate electrode GE, and first and second conductiveregions (for example, source and drain regions) disposed on both sidesof the channel region.

The gate insulating layer GI may be disposed on the semiconductor layer.For example, a second conductive layer may be disposed on the gateinsulating layer GI.

The second conductive layer may include the gate electrode GE of eachtransistor TR. For example, the second conductive layer may furtherinclude one electrode and/or a predetermined line of the storagecapacitor Cst.

The first interlayer insulating layer ILD1 may be disposed on the secondconductive layer. For example, a third conductive layer may be disposedon the first interlayer insulating layer ILD1.

The third conductive layer may include first and second transistorelectrodes TE1 and TE2 of each transistor TR. Here, the first and secondtransistor electrodes TE1 and TE2 may be source and drain electrodes SEand DE. For example, the third conductive layer may further include oneelectrode and/or a predetermined line of the storage capacitor Cst.

The second interlayer insulating layer ILD2 may be disposed on the thirdconductive layer. For example, a fourth conductive layer may be disposedon the second interlayer insulating layer ILD2.

The fourth conductive layer may include the bridge pattern BRPelectrically connecting the circuit layer PCL and the display layer DPLand/or a predetermined line (for example, the first power line PL1and/or the second power line PL2). The bridge pattern BRP may beelectrically connected to the first electrode ELT1 of the light emittingunit EMU through the first contact hole CH1 or the like within thespirit and the scope of the disclosure. The second power line PL2 may beelectrically connected to the second electrode ELT2 of the lightemitting unit EMU through the second contact hole CH2 or the like withinthe spirit and the scope of the disclosure.

The passivation layer PSV may be disposed on the fourth conductivelayer. According to an embodiment, the passivation layer PSV may includeat least an organic insulating layer and may substantially planarize asurface of the circuit layer PCL. The display layer DPL may be disposedon the passivation layer PSV.

The display layer DPL may include the light emitting unit EMU of eachpixel PXL. For example, the display layer DPL may include the first andsecond electrodes ELT1 and ELT2 disposed in the light emitting area EMAof each pixel PXL, the plurality of light emitting elements LDelectrically connected between the first and second electrodes ELT1 andELT2, and the first and second contact electrodes CNE1 and CNE2electrically connecting the first and second electrodes ELT1 and ELT2and the light emitting elements LD.

Meanwhile, FIGS. 5A and 5B show each light emitting element LD, as inthe embodiments of FIGS. 3 to 4B, each pixel PXL may include theplurality of light emitting elements LD electrically connected in theforward direction between the first and second electrodes ELT1 and ELT2.Therefore, in describing embodiments of FIGS. 5A and 5B and otherembodiments to be described later, each embodiment may be describedunder an assumption that the pixel PXL may include the plurality oflight emitting elements LD.

For example, the display layer DPL may further include the first bankBNK1 for protruding one region of the first and second electrodes ELT1and ELT2 in the upward direction, and the second bank BNK2 surroundingeach light emitting area EMA. For example, the display layer DPL mayfurther include at least one conductive layer, an insulating layer,and/or the like within the spirit and the scope of the disclosure.

For example, the display layer DPL may include the first bank BNK1, thefirst and second electrodes ELT1, ELT2, a first insulating layer INS1,the light emitting elements LD, an insulating pattern INP, the first andsecond contact electrodes CNE1 and CNE2, and a third insulating layerINS3 sequentially disposed and/or formed or disposed on the circuitlayer PCL.

In an embodiment, the first and second contact electrodes CNE1 and CNE2may be disposed on the same layer as shown in FIG. 5A. In an embodiment,the first and second contact electrodes CNE1 and CNE2 may be disposedseparately in different layers as shown in FIG. 5B. In this case, thedisplay layer DPL may further include a second insulating layer INS2interposed between the first and second contact electrodes CNE1 andCNE2. For example, the second insulating layer INS2 may cover or overlapthe first contact electrode CNE1, and one end of the second insulatinglayer INS2 may be interposed between the first contact electrode CNE1and the second contact electrode CNE2.

Meanwhile, in a case of the second bank BNK2, a position on the crosssection may vary according to an embodiment. In an embodiment, thesecond bank BNK2 may be formed or disposed on the first insulating layerINS1. In an embodiment, the second bank BNK2 may be disposed on the samelayer as the first bank BNK1. For example, the second bank BNK2 may ormay not overlap the first bank BNK1.

The first bank BNK1 may be disposed on one or a surface of the baselayer BSL on which the circuit layer PCL may be selectively formed ordisposed. The first bank BNK1 may protrude in the height direction ofthe base layer BSL on one surface of the base layer BSL on which thecircuit layer PCL may be formed or disposed. Accordingly, one region ofthe first and second electrodes ELT1 and ELT2 disposed on the first bankBNK1 may protrude in the upward direction.

A reflective partition wall may be formed around the light emittingelements LD by the first bank BNK1 and the first and second electrodesELT1 and ELT2 disposed on the first bank BNK1. Accordingly, the lightefficiency of the pixel PXL may be improved.

The first bank BNK1 may have various shapes. In an embodiment, the firstbank BNK1 may be formed to have an inclined surface inclined at apredetermined range of angle with respect to the base layer BSL as shownin FIGS. 5A and 5B. In an embodiment, the first bank BNK1 may havesidewalls such as a substantially curved surface or a substantiallystepped shape. For example, the first bank BNK1 may have a cross sectionsubstantially of a semicircle or semi-ellipse shape, and the like withinthe spirit and the scope of the disclosure.

The first and second electrodes ELT1 and ELT2 forming pixel electrodesof each pixel PXL may be disposed on the first bank BNK1. According toan embodiment, the first and second electrodes ELT1 and ELT2 may have ashape substantially corresponding to the first bank BNK1. For example,the first and second electrodes ELT1 and ELT2 may protrude in the heightdirection of the base layer BSL by the first bank BNK1.

Each of the first and second electrodes ELT1 and ELT2 may include atleast one conductive material. For example, the first and secondelectrodes ELT1 and ELT2 may include the same or different conductivematerials. For example, each of the first and second electrodes ELT1 andELT2 may be formed of a single layer or multiple layers.

The first insulating layer INS1 may be disposed on one region of thefirst and second electrodes ELT1 and ELT2. For example, the firstinsulating layer INS1 may be formed to cover or overlap one region ofeach of the first and second electrodes ELT1 and ELT2, and may includean opening exposing another region of each of the first and secondelectrodes ELT1 and ELT2. For example, the first insulating layer INS1may include a plurality of openings formed on an upper surface of thefirst bank BNK1. In an embodiment, the first insulating layer INS1 mayalso include a plurality of contact holes formed at respectiveconnection points, which may be for electrically connecting the firstand second electrodes ELT1 and ELT2 to the first and second contactelectrodes CNE1 and CNE2, respectively.

In a region where the first insulating layer INS1 is opened, the firstand second electrodes ELT1 and ELT2 may be electrically connected to thefirst and second contact electrodes CNE1 and CNE2, respectively.Meanwhile, the first insulating layer INS1 may be omitted according toan embodiment. In this case, the light emitting elements LD may bedirectly disposed on one end of each of the passivation layer PSV and/orthe first and second electrodes ELT1 and ELT2.

In an embodiment, the first insulating layer INS1 may be formed ordisposed to entirely cover or overlap the first and second electrodesELT1 and ELT2. After the light emitting elements LD may be supplied andaligned on the first insulating layer INS1, the first insulating layerINS1 may be partially opened to expose one or a region of the first andsecond electrodes ELT1 and ELT2. Since the first and second electrodesELT1 and ELT2 may be formed or disposed and then covered or overlappedby the first insulating layer INS1 or the like, the first and secondelectrodes ELT1 and ELT2 may be prevented from being damaged in asubsequent process.

The light emitting elements LD may be supplied and aligned in the lightemitting area EMA in which the first insulating layer INS1 or the likemay be formed or disposed. Meanwhile, prior to the supply of the lightemitting elements LD, the second bank BNK2 may be formed or disposedaround the light emitting area EMA. For example, the second bank BNK2may be formed or disposed in the display area DA to surround each lightemitting area EMA.

In an embodiment, at least some or a predetermined number of the lightemitting elements LD may be disposed in a horizontal direction, adiagonal direction, or the like between a pair of first and secondelectrodes ELT1 and ELT2 so that the both end portions (for example, thefirst and second end portions EP1 and EP2) of a longitudinal directionthereof overlap neighboring pair of first and second electrodes ELT1 andELT2. In an embodiment, at least some or a predetermined number of thelight emitting elements LD may be disposed between the neighboring pairof first and second electrodes ELT1 and ELT2 so as not to overlap thefirst and second electrodes ELT1 and ELT2, and may be electricallyconnected to the pair of first and second electrodes ELT1 and ELT2through the first and second contact electrodes CNE1 and CNE2,respectively. For example, according to an embodiment, the lightemitting elements LD may or may not overlap the first electrode ELT1and/or the second electrode ELT2, and may be electrically connectedbetween the first and second electrodes ELT1 and ELT2 by the first andsecond contact electrodes CNE1 and CNE2.

The insulating pattern INP may be disposed on one region of the lightemitting elements LD. For example, the insulating pattern INP may belocally disposed on one region of the light emitting elements LD toexpose the first and second end portions EP1 and EP2 of each of thelight emitting elements LD.

The insulating pattern INP may be formed of a single layer or multiplelayers, and may include at least one inorganic insulating materialand/or organic insulating material. For example, the insulating patternINP may include various types of organic/inorganic insulating materialsincluding silicon nitride (SiNx) or silicon oxide (SiOx).

In a case that the insulating pattern INP may be formed or disposed onthe light emitting elements LD after the alignment of the light emittingelements LD is completed, the light emitting elements LD may beprevented from deviating from an aligned position.

In an embodiment, in a case that a spaced apart space may be presentbetween the first insulating layer INS1 and the light emitting elementsLD due to a step difference formed by the first and second electrodesELT1 and ELT2, the spaced apart space may be partially or completelyfilled by an insulating material flowed in a process of forming theinsulating pattern INP. Accordingly, the light emitting elements LD maybe more stably supported.

The both end portions of the light emitting elements LD, which may notbe covered or overlap by the insulating pattern INP, for example, thefirst and second end portions EP1 and EP2, may be covered or overlappedby the first and second contact electrodes CNE1 and CNE2, respectively.The first and second contact electrodes CNE2 and CNE2 may be formed ordisposed to be spaced apart from each other. For example, the first andsecond contact electrodes CNE1 and CNE2 may be disposed with theinsulating pattern INP interposed therebetween, and may be disposed tobe spaced apart from each other on the first and second end portions EP1and EP2 of at least one light emitting element LD.

For example, the first and second contact electrodes CNE1 and CNE2 maybe disposed on the first and second electrodes ELT1 and ELT2 to cover oroverlap exposed regions of the first and second electrodes ELT1 andELT2. For example, the first and second contact electrodes CNE1 and CNE2may be disposed at least one region of each of the first and secondelectrodes ELT1 and ELT2 to be directly/indirectly in contact with eachof the first and second electrodes ELT1 and ELT2 on the first bank BNK1or around the first bank BNK1.

Accordingly, the first and second contact electrodes CNE1 and CNE2 maybe electrically connected to the first and second electrodes ELT1 andELT2, respectively. For example, each of the first and second electrodesELT1 and ELT2 may be electrically connected to the first end portion EP1or the second end portion EP2 of at least one adjacent light emittingelement LD through the first and second contact electrodes CNE1 andCNE2.

In a case that the first and second contact electrodes CNE1 and CNE2 maybe formed on the same layer as in an embodiment of FIG. 5A, the firstand second contact electrodes CNE1 and CNE2 may be formed simultaneouslyin the same process, or may be sequentially formed, and the secondinsulating layer INS2 may be omitted. In this case, a manufacturingprocess of the pixel PXL may be simplified.

Meanwhile, as in an embodiment of FIG. 5B, the first and second contactelectrodes CNE1 and CNE2 may be formed or disposed in different layerson one surface of the base layer BSL. For example, the second insulatinglayer INS2 may be interposed between the first and second contactelectrodes CNE1 and CNE2.

The second insulating layer INS2 may be disposed to cover or overlap anyone (for example, the first contact electrode CNE1) of the first andsecond contact electrodes CNE1 and CNE2. In a case that the insulatingpattern INP and/or the second insulating layer INS2 may be formed ordisposed on the light emitting elements LD, electrical stability betweenthe first and second end portions EP1 and EP2 of the light emittingelements LD may be ensured. Accordingly, a short defect may be preventedfrom occurring between the first and second end portions EP1 and EP2 ofthe light emitting elements LD.

The first and second contact electrodes CNE1 and CNE2 may be formed ofvarious transparent conductive materials. For example, the first andsecond contact electrodes CNE1 and CNE2 may include at least one ofvarious transparent conductive materials including ITO, IZO, ITZO, ZnO,AZO, GZO, ZTO, GTO, and FTO, and may be implemented to be substantiallytransparent or translucent to satisfy a predetermined transmittance.Accordingly, the light emitted from the light emitting elements LDthrough each of the first and second end portions EP1 and EP2 may passthrough the first and second contact electrodes CNE1 and CNE2 and may beemitted to the outside of the display panel PNL.

The third insulating layer INS3 may be disposed on the first and secondcontact electrodes CNE1 and CNE2. For example, third insulating layerINS3 may be entirely formed and/or disposed on the display area DA tocover or overlap the first and second banks BNK1 and BNK2, the first andsecond electrodes ELT1 and ELT2, the first and/or second insulatinglayers INS1 and/or INS2, the light emitting elements LD, the insulatingpattern INP, and the first and second contact electrodes CNE1 and CNE2.The third insulating layer INS3 may include an inorganic film and/ororganic film of at least one layer.

In an embodiment, the third insulating layer INS3 may include a thinfilm encapsulation layer of a multi-layer structure. For example, thethird insulating layer INS3 may be formed of a thin film encapsulationlayer of a multi-layer structure including inorganic insulating layersof a plurality of layers and an organic insulating layer of at least onelayer interposed between the inorganic insulating layers. However, theconfiguration material and/or the structure of the third insulatinglayer INS3 may be variously changed. For example, according to anembodiment, an overcoat layer of at least one layer, a filler, an uppersubstrate, and/or the like may be further disposed on the thirdinsulating layer INS3.

FIGS. 6 and 7 are a plan view and a schematic cross-sectional viewillustrating a method of supplying the light emitting elements LD to thepixels PXL according to an embodiment. For example, FIGS. 6 and 7illustrate an embodiment of a method of supplying the light emittingelements LD to each pixel PXL using inkjet printing equipment includingan inkjet head IHD in which a plurality of nozzles NZL may be installed.

Referring to FIGS. 6 and 7, the inkjet head IHD may include theplurality of nozzles NZL to simultaneously supply the light emittingelements LD to the plurality of pixels PXL. For example, the inkjet headIHD may include the nozzles NZL corresponding to the plurality of pixelsPXL sequentially arranged or disposed in one or a pixel row.

According to an embodiment, the nozzles NZL may be arranged or disposedat a pitch similar to or identical to that of the pixels PXL, and eachnozzle NZL may supply a light emitting element ink LIK of a fixedquantity to each pixel PXL within a predetermined error range. Here, thelight emitting element ink LIK may mean a solution in which a pluralityof light emitting elements LD may be mixed.

The inkjet head IHD may sequentially supply the light emitting elementink LIK to pixel blocks PXB arranged or disposed in the display area DAwhile simultaneously supplying the light emitting element ink LIK to thepixels PXL in a unit of the pixel block PXB including the pixels PXL ofthe number corresponding to the number of nozzles NZL. In an embodiment,the inkjet head IHD may alternately move along the first direction DR1and the second direction DR2 to supply the light emitting element inkLIK to all pixel areas PXA of the base layer BSL, on one or a surface ofthe base layer BSL on which the first and second electrodes ELT1 andELT2 and the second bank BNK2 may be formed or disposed.

An average number of light emitting elements LD supplied to each pixelarea PXA (for example, each light emitting area EMA) may vary by aconcentration of the light emitting element ink LIK supplied to thepixel area PXA. For example, each pixel PXL may have an effective lightsource corresponding to (for example, proportional to) the number oflight emitting elements LD supplied to a corresponding pixel area PXA.For example, as the number of light emitting elements LD supplied toeach pixel area PXA increases, the number of light emitting elements LDelectrically connected in the forward direction between the first andsecond electrodes ELT1 and ELT2 may be increased.

The number of effective light sources, for example, the number of lightemitting elements LD electrically connected in the forward direction mayaffect a light emission characteristic of each pixel PXL. For example,in consideration of the area of the pixel area PXA and/or a probabilityof occurrence of a short defect, a supply amount of the light emittingelement ink LIK may be adjusted so that the light emitting elements LDof a predetermined number range may be supplied to each pixel area PXA.Accordingly, each pixel PXL may include the light emitting elements LDthat may not be saturated. In this case, even though a uniform drivingcurrent may flow through the pixels PXL in correspondence with each datavoltage, in a case that a number deviation of the light emittingelements LD may occur, the pixels PXL may exhibit a luminance deviation.Therefore, in order for the pixels PXL disposed in the display area DAto exhibit a uniform luminance characteristic, the light emittingelements LD of a uniform number range may be required to be supplied toeach pixel area PXA.

However, in a case that the inkjet head IHD may have a shape extendingalong one or a direction, for example, the second direction DR2, theconcentration of the light emitting element ink LIK supplied to eachnozzle NZL may decrease toward both ends of the inkjet head IHD.Accordingly, even though a uniform amount of light emitting element inkLIK may be supplied to the pixels PXL of each pixel block PXB, arelatively less number of light emitting elements LD may be supplied tothe pixels PXL that may receive the light emitting element ink LIK fromthe nozzles NZL positioned or disposed at the both ends of the inkjethead IHD compared to the remaining pixels PXL. Thus, a streak stain mayoccur in the display area DA along a region where the both ends of theinkjet head IHD may pass.

In describing the following embodiment, each pixel PXL receiving arelatively less number of light emitting elements LD and thus includinga relatively less number of light emitting elements LD may be referredto as a “first pixel PXL1”. For example, each of the remaining pixelsPXL except for the first pixels PXL1, which may be pixels PXL includinga relatively great number of light emitting elements LD compared to thefirst pixels PXL1, may be referred to as a “second pixel PXL2”.

For example, the pixels PXL may be divided into the first pixels PXL1and the second pixels PXL2 according to a number range of the lightemitting elements LD (for example, the effective light emitting elementsLD) arranged or disposed in each light emitting area EMA and/orpositions of each pixel PXL within each pixel block PXB. For example,the light emitting areas EMA of the first pixel PXL1 and the secondpixel PXL2 may be referred to as a “first light emitting area EMA1” anda “second light emitting area EMA2”, respectively, and the lightemitting elements LD of the first pixel PXL1 and the second pixel PXL2may be referred to as “first light emitting elements LD1” and “secondlight emitting elements LD2”, respectively.

For example, the first pixel PXL1 and the second pixel PXL2 may bereferred to by classifying the pixels PXL by different referencesseparately from a color of each pixel PXL, and each first pixels PXL1may be the first color pixel CPX1, the second color pixel CPX2, or thethird color pixel CPX3. Similarly, each second pixel PXL2 may be thefirst color pixel CPX1, the second color pixel CPX2, or the third colorpixel CPX3.

Meanwhile, in describing an embodiment, the pixels PXL may be divided totwo groups of the first pixels PXL1 and the second pixels PXL2 accordingto the number range of the light emitting elements LD and/or thepositions within the pixel block PXB, but the disclosure is not limitedthereto. For example, in an embodiment, the pixels PXL may be dividedinto three or more groups by subdividing the number range of the lightemitting elements LD included in each of the pixels PXL and/or thepositions of the pixels PXL within each pixel block PXB.

As described above, in a case that a relatively less number of lightemitting elements LD may be supplied to the first pixels PXL1 positionedat both ends of each pixel block PXB, the first pixels PXL1 may exhibita relatively low luminance characteristic compared to the second pixelsPXL2. For example, even though a data signal of the same voltage may beapplied to the first pixels PXL1 and the second pixels PXL2, the firstpixels PXL1 may emit light at a luminance lower than that of the secondpixels PXL2. Accordingly, a luminance may be reduced in the first pixelsPXL1 positioned at both end ends of the pixel blocks PXB, and thus astreak stain may occur in the display area DA.

In order to prevent the occurrence of such a streak stain, by supplyingthe light emitting element ink LIK to each pixel PXL over a plurality oftimes, a sufficient number of light emitting elements LD (the firstlight emitting elements LD1) may also be supplied to the first pixelsPXL1. However, in this case, a possibility of occurrence of the shortdefect due to the light emitting elements LD may increase. Accordingly,in an embodiment to be described later, a method capable of easilyalleviating or preventing a luminance deviation of the pixels PXLaccording to the number deviation of the light emitting elements LDwithout increasing the number of times the light emitting element inkLIK is supplied is proposed.

FIG. 8 is a plan view illustrating the pixel block PXB according to anembodiment. For example, FIG. 8 illustrates one pixel block PXBsimultaneously receiving the light emitting elements LD by the nozzlesNZL installed in the inkjet head IHD in an embodiment of FIGS. 6 and 7.

FIG. 9A is a plan view illustrating the first pixel PXL1 of FIG. 8, andFIG. 9B is a plan view illustrating the second pixel PXL2 of FIG. 8. Forexample, the first pixel PXL1 of FIG. 9A may be any one of the firstcolor first pixel CPX11, the second color first pixel CPX12, and thethird color first pixel CPX13 of FIG. 8, and the second pixel PXL2 ofFIG. 9B may be any one of the first color second pixel CPX21, the secondcolor second pixel CPX22, and the third color second pixel CPX23 of FIG.8.

First, referring to FIG. 8, one first pixel unit PXU1 may be disposed ateach of the both ends of the pixel block PXB, and second pixel unitsPXU2 may be disposed between the first pixel units PXU1. According to anembodiment, each first pixel unit PXU1 may include first pixels PXL1 ofdifferent colors, and each second pixel unit PXU2 may include secondpixels PXL2 of different colors. For example, each first pixel unit PXU1may include the first color first pixel CPX11, the second color firstpixel CPX12, and the third color first pixel CPX13, and each secondpixel unit PXU2 may include the first color second pixel CPX21, thesecond color second pixel CPX22, and the third color second pixel CPX23.

Meanwhile, in an embodiment, one first pixel unit PXU1 may be disposedat each of the both ends of the pixel block PXB, but the disclosure isnot limited thereto. For example, the number of first pixel units PXU1disposed at one or an end of the pixel block PXB may be changed. Forexample, at least two or more pixel units PXU may be classified as thepixel units PXU1 on at least one or an end of the pixel block PXBaccording to the number of light emitting elements LD arranged ordisposed in each pixel PXL and/or a deviation range thereof.

For example, in an embodiment, the first pixels PXL1 and the secondpixels PXL2 may be divided in a unit of the pixel unit PXU, but thedisclosure is not limited thereto. For example, regardless of the colorof each pixel PXL, at least one or more pixels PXL may be classified asthe first pixel PXL1 on at least one end of the pixel block PXBaccording to the number of light emitting elements LD arranged ordisposed in the pixel PXL and/or a deviation range thereof.

Referring to FIGS. 9A and 9B, each first pixel PXL1 (the first colorfirst pixel CPX11, the second color first pixel CPX12, or the thirdcolor first pixel CPX13) may include the light emitting elements LD of anumber less than that of each second pixel PXL2 (the first color secondpixel CPX21, the second color second pixel CPX22, or the third colorsecond pixel CPX23). For example, the first light emitting elements LD1of a first number may be arranged or disposed in the pixel area PXA1(for example, the first light emitting area EMA1) of the first pixelPXL1, and the second light emitting elements LD2 of a second numbergreater than the first number may be arranged or disposed in the pixelarea PXA2 (for example, the second light emitting area EMA2) of thesecond pixel PXL2.

The first light emitting elements LD1 may be arranged or disposed in theforward direction between the first and second electrodes ELT1 and ELT2in the first light emitting area EMA1. Accordingly, the first lightemitting elements LD1 may form a light source of the first pixel PXL1.

The second light emitting elements LD2 may be arranged or disposed inthe forward direction between the first and second electrodes ELT1 andELT2 in the second light emitting area EMA2. Accordingly, the secondlight emitting elements LD2 may form a light source of the second pixelPXL2.

According to an embodiment, a light blocking pattern covering oroverlapping a peripheral area of the first and second light emittingareas EMA1 and EMA2, which is the non-light emitting area NEA may bedisposed on the first and second pixels PXL1 and PXL2. The lightblocking pattern may be opened by different areas on the first pixelPXL1 and the second pixel PXL2 a luminance deviation of the first andsecond pixels PXL1 and PXL2 according to the number deviation of thefirst and second light emitting devices LD1 and LD2 may be reduced orcanceled. Meanwhile, in a case that the pixels PXL may be divided intothree or more groups by more subdividing the number range of the lightemitting elements LD included in each of the pixels PXL and/or thepositions of the pixels PXL, different aperture ratios may be applied tothe three or more groups. An embodiment related to a method of adjustingthe aperture ratio of the pixels PXL is described later.

FIGS. 10A to 10E are plan views each illustrating a color filter CF anda light blocking pattern LBP according to an embodiment. For example,FIGS. 10A to 10D illustrate different embodiments of the color filter CFand the light blocking pattern LBP that may be disposed on the pixelblock PXB of FIG. 8. For example, FIG. 10E illustrates a structure inwhich the color filter CF and the light blocking pattern LBP accordingto any one of the embodiments of FIGS. 10A to 10D, for example, anembodiment of FIG. 10B is disposed in the display area DA of FIG. 6.

First, referring to FIGS. 6 to 10A, the light blocking pattern LBP mayinclude a plurality of openings OPN separated and opened to correspondto the light emitting area EMA of each pixel PXL. For example, the lightblocking pattern LBP may include first openings OPN1 corresponding tothe first light emitting areas EMA1 of the first pixels PXL1 and secondopenings OPN2 corresponding to the second light emitting areas EMA2 ofthe second pixels PXL2, and may be disposed on the first and secondpixels PXL1 and PXL2 to cover or overlap the peripheral area of thefirst and second light emitting areas EMA1 and EMA2. For example, thelight blocking pattern LBP may include first openings OPN1 exposing thefirst light emitting areas EMA1 of the first to third color first pixelsCPX11, CPX12, and CPX13 and second openings OPN2 exposing the secondlight emitting areas EMA2 of the first to third color second pixelsCPX21, CPX22, and CPX23, and may be disposed on the first and secondpixels PXL1 and PXL2 to cover or overlap an edge area of the first andsecond light emitting areas EMA1 and EMA2 and/or the non-light emittingarea NEA around or adjacent to the edge area.

The openings OPN of the light blocking pattern LBP may have a shapeand/or a size substantially corresponding to each pixel area PXA, forexample, each light emitting area EMA. For example, each of the firstand second openings OPN1 and OPN2 may have a shape extending along thefirst direction DR1 and may be arranged or disposed spaced apart fromeach other along the second direction DR2 in a region corresponding toeach pixel block PXB.

The color filter pattern CFP corresponding to each pixel PXL may bedisposed in each opening OPN of the light blocking pattern LBP. Forexample, first color filter patterns CFP1 corresponding to a color ofeach first pixel PXL1 may be disposed in the first openings OPN1 on thefirst pixels PXL1, and second color filter patterns CFP2 correspondingto a color of each second pixel PXL2 may be disposed in the secondopenings OPN2 on the second pixels PXL2.

For example, a first color first color filter pattern CFP11, a secondcolor first color filter pattern CFP12, and a third color first colorfilter pattern CFP13 may be disposed in the first openings OPN1positioned or disposed on the first color first pixel CPX11, the secondcolor first pixel CPX12, and the third color first pixel CPX13,respectively. For example, a first color second pixel CPX21, a secondcolor second pixel CPX22, and a third color second pixel CPX23 may bedisposed in the second openings OPN2 positioned or disposed on the firstcolor second pixel CPX21, the second color second pixel CPX22, and thethird color second pixel CPX23, respectively.

The first and second color filter patterns CFP1 and CFP2 may have ashape and/or a size substantially corresponding to each pixel area PXA,for example, each light emitting area EMA. For example, each of thefirst and second color filter patterns CFP1 and CFP2 may have a shapeextending along the first direction DR1 and may be arranged or disposedspaced apart from each other along the second direction DR2 in theregion corresponding to each pixel block PXB.

Meanwhile, in a case that dividing the color filter patterns CFP basedon each color regardless of the first and second pixels PXL1 and PXL2,the color filter patterns CFP may be collectively referred to as first,second, or third color filters CF1, CF2, or CF3. For example, a colorfilter pattern of a first color (for example, the first color firstcolor filter pattern CFP11 and the first color second color filterpattern CFP21) may be collectively referred to as the “first colorfilter CF1”, a color filter pattern of a second color (for example, thesecond color first color filter pattern CFP12 and the second colorsecond color filter pattern CFP22) may be collectively referred to asthe “second color filter CF2”, and a color filter pattern of a thirdcolor (for example, the third color first color filter pattern CFP13 andthe third color second color filter pattern CFP23) may be collectivelyreferred to as the “third color filter CF3”. For example, the firstcolor filter CF1 may be disposed on each first color pixel CPX1, thesecond color filter CF2 may be disposed on each second color pixel CPX2,and the third color filter CF3 may be disposed on each third color pixelCPX3.

In an embodiment, the first and second pixels PXL1 and PXL2 may have auniform aperture ratio. For example, the light blocking pattern LBP maybe opened in a uniform size (for example, a uniform area) on each of thefirst pixel PXL1 and the second pixel PXL2 regardless of the division ofthe first and second pixels PXL1 and PXL2. In this case, the first andsecond openings OPN1 and OPN2 may have a uniform size in the entiredisplay area DA. For example, the first and second color filter patternsCFP1 and CFP2 may have a size corresponding to each opening OPN, andthus the first and second color filter patterns CFP1 and CFP2 may have auniform size in the entire display area DA.

In an embodiment, the first and second pixels PXL1 and PXL2 may have auniform aperture ratio, and may have an aperture ratio adjusted for eachcolor group in consideration of light emission efficiency, whitebalance, a visibility characteristic, and/or the like according toexternal light reflection. For example, the first color first pixelCPX11, the second color first pixel CPX12, and/or the third color firstpixel CPX13 forming each first pixel unit PXU1 may have differentaperture ratios. Similarly, the first color second pixel CPX21, thesecond color second pixel CPX22, and/or the third color second pixelCPX23 forming each second pixel unit PXU2 may have different apertureratios. For example, the light blocking pattern LBP may have openingsOPN of different sizes (areas) for each color group of the pixels PXL.In this case, the color filters CF disposed in each opening OPN may alsohave different sizes (areas) for each color group. For example, thefirst color filter CF1, the second color filter CF2, and/or the thirdcolor filter CF3 may have different sizes.

According to an embodiment, the pixels PXL of the same color may have auniform aperture ratio. For example, the first color first pixel CPX11and the first color second pixel CPX21 may have substantially the sameor similar aperture ratio, the second color first pixel CPX12 and thesecond color second pixel CPX22 may have substantially the same orsimilar aperture ratio, and the third color first pixel CPX13 and thethird color second pixel CPX23 may have substantially the same orsimilar aperture ratio.

In an embodiment of FIG. 10A, regardless of the division of the firstand second pixels PXL1 and PXL2, the pixels PXL may have generallyuniform aperture ratio or an aperture ratio adjusted for each colorgroup. However, in this case, a luminance deviation between the firstand second pixels PXL1 and PXL2 may occur due to the number variation ofthe light emitting elements LD arranged or disposed in the first andsecond pixels PXL1 and PXL2, and thus image quality of the displaydevice may be reduced.

Accordingly, in an embodiment, the aperture ratio of the first andsecond pixels PXL1 and PXL2 may be adjusted so that the luminancedeviation between the first and second pixels PXL1 and PXL2 may bereduced or prevented.

Referring to FIGS. 6 to 9B and 10B to 10E, within at least one colorgroup, the first pixels PXL1 and the second pixels PXL2 may havedifferent aperture ratios. For example, according to an embodiment,regardless of the color group, the first pixels PXL1 and the secondpixels PXL2 may have different aperture ratios. For example, in anembodiment, the aperture ratios of the first pixels PXL1 and the secondpixels PXL2 may be set differentially so that the luminance deviationbetween the first and second pixels PXL1 and PXL2 due to the numbervariation of the light emitting elements LD may be reduced or prevented.

For example, within a specific or predetermined color group or aplurality of color groups, the second pixel PXL2 including the secondlight emitting elements LD2 of the number greater than that of the firstlight emitting elements LD1 arranged or disposed in the first pixel PXL1may have an aperture ratio lower than that of the first pixel PXL1. Forexample, each second opening OPN2 disposed on each second pixel PXL2 mayhave the area less than that of each first opening OPN1 disposed on eachfirst pixel PXL1. To this end, in at least one of the first directionDR1 and the second direction DR2, the second openings OPN2 may have alength (and/or a width) shorter than that of the first openings OPN1.

For example, the second openings OPN2 may have a length Lo2 shorter thana length Lo1 of the first openings OPN1 in the first direction DR1 whichmay be a long side as shown in FIGS. 10B and 10E. In an embodiment, thesecond openings OPN2 may have a width Wo2 shorter than a width Wo1 ofthe first openings OPN1 on the second direction DR2 which may be a shortside direction as shown in FIG. 10C. In an embodiment, the secondopenings OPN2 may have the length Lo2 shorter than the length Lo1 of thefirst openings OPN1 on the first direction DR1 and may have the widthWo2 shorter than the width Wo1 of the first openings OPN1 on the seconddirection DR2 as shown in FIG. 10D.

Similarly, within a specific or predetermined color group or a pluralityof color groups, each second color filter pattern CFP2 disposed on eachsecond pixel PXL2 may have the area less than that of each first colorfilter pattern CFP1 disposed on each first pixel PXL1. To this end, inat least one of the first direction DR1 and the second direction DR2,the second color filter patterns CFP2 may have a length (and/or a width)shorter than that of the first color filter patterns CFP1.

For example, the second color filter patterns CFP2 may have a length Lc2shorter than a length Lc1 of the first color filter patterns CFP1 on thefirst direction DR1 as shown in FIGS. 10B and 10E. In an embodiment, thesecond color filter patterns CFP2 may have a width Wc2 shorter than awidth Wc1 of the first color filter patterns CFP1 in the seconddirection DR2 as shown in FIG. 10C. In an embodiment, the second colorfilter patterns CFP2 may have the length Lc2 shorter than the length Lc1of the first color filter patterns CFP1 in the first direction DR1 andmay have the width Wc2 shorter than the width Wc1 of the first colorfilter patterns CFP1 in the second direction DR2 as shown in FIG. 10D.

The display device according to the above-described embodiment mayinclude the first pixel PXL1 and the second pixel PXL2 includingdifferent numbers of light emitting elements LD, and the light blockingpattern LBP opened by a less area on the pixel PXL (for example, thesecond pixel PXL2) including a larger number of light emitting elementsLD. The luminance of each pixel PXL may be proportional to the number ofthe light emitting elements LD and the aperture ratio. Therefore, in acase that the aperture ratio of the pixel PXL including the largernumber of light emitting elements LD is relatively decreased, and/or theaperture ratio of the pixel PXL including the less number of lightemitting elements LD is relatively increased, the luminance deviation ofthe pixels PXL may be reduced or prevented.

For example, in the above-described embodiment, the aperture ratio ofthe pixels PXL may be adjusted according to the number deviation of thelight emitting elements LD arranged or disposed in each pixel PXL.Accordingly, by causing the luminance of the pixels PXL to be uniform,the streak stain may be prevented and the image quality of the displaydevice may be improved.

FIGS. 11A and 11B are schematic cross-sectional views each illustratingthe display device according to an embodiment. For example, FIG. 11Adiscloses an embodiment of a display panel PNL that does not includecolor conversion particles (for example, red and green quantum dots QDrand QDg), and FIG. 11B disclosure an embodiment of a display panel PNLincluding the color conversion particles. For example, the displaydevice according to the disclosure may selectively include the colorconversion particles disposed on the pixels PXL.

In FIGS. 11A and 11B, a cross section of the display panel PNL is shown,based on a region in which one pixel unit PXU formed of the first colorpixel CPX1, the second color pixel CPX2, and the third color pixel CPX3adjacent to each other is disposed. Meanwhile, since the examplestructure of each pixel PXL has been described in detail through theabove-described embodiments, the structure of each pixel PXL isschematically shown in FIGS. 11A and 11B, and detailed descriptionthereof may be omitted. For example, FIGS. 11A and 11B schematicallyshow the cross section along the second direction DR2 with respect tothe display panel PNL on which the pixel unit PXU shown in FIG. 2 may bedisposed.

First, referring to FIGS. 2 to 11A, the light emitting unit EMU of eachpixel PXL may be disposed on the display layer DPL on the base layer BSLand/or the circuit layer PCL. For example, the light emitting unit EMUof the corresponding pixel PXL may be disposed in each light emittingarea EMA of the display layer DPL. For example, in each light emittingarea EMA, the first and second pixel electrodes ELT1 and ELT2, the lightemitting elements LD, the first and second contact electrodes CNE1 andCNE2, and the first and the second banks BNK1 and BNK2 may be disposed,and at least one insulating layer may be further disposed. For example,an overcoat layer, a filler, or the like may be selectively disposed onthe display layer DPL.

In an embodiment, the first, second, and third color pixels CPX1, CPX2,and CPX3 may include light emitting elements LD that emit light ofdifferent colors. For example, the first color, second color, and thirdcolor pixels CPX1, CPX2, and CPX3 may include first color light emittingelements LDr, second color light emitting elements LDg, and third colorlight emitting elements LDb, respectively.

The first color light emitting elements LDr may be red light emittingelements that emit light of a first color, for example, red, the secondcolor light emitting elements LDg may be green light emitting elementsthat emit light of green, and the third color light emitting elementsLDb may be blue light emitting elements that emit light of blue.However, the color of the light emitted from each light emitting elementLD may vary according to an embodiment.

According to an embodiment, an upper substrate UPL may be disposed onthe pixels PXL. For example, the upper substrate UPL (also referred toas an “encapsulation substrate” or a “color filter substrate”)encapsulating the display area DA may be disposed on one surface of thebase layer BSL on which the pixels PXL may be disposed.

The upper substrate UPL may selectively include a light control layerLCP overlapping the pixels PXL. For example, the light control layer LCPincluding a color filter layer CFL may be disposed on one surface of theupper substrate UPL facing the pixels PXL.

The color filter layer CFL may include a color filter CF matching acolor of each pixel PXL. For example, the color filter layer CFL mayinclude a first color filter CF1 disposed on the first color pixel CPX1to selectively transmit light generated in the first color pixel CPX1, asecond color filter CF2 disposed on the second color pixel CPX2 toselectively transmit light generated in the second color pixel CPX2, anda third color filter CF3 disposed on the third color pixel CPX3 toselectively transmit light generated in the third color pixel CPX3. Inan embodiment, the first color filter CF1, the second color filter CF2,and the third color filter CF3 may be a red color filter, a green colorfilter, a and blue color filter, respectively, but are not limitedthereto.

The first color filter CF1 may include a color filter material disposedbetween the first color pixel CPX1 and the upper substrate UPL andselectively transmitting light of a first color generated in the firstcolor pixel CPX1. For example, in a case that the first color pixel CPX1may be a red pixel, the first color filter CF1 may include a red colorfilter material.

The second color filter CF2 may include a color filter material disposedbetween the second color pixel CPX2 and the upper substrate UPL andselectively transmitting light of a second color generated in the secondcolor pixel CPX2. For example, in a case that the second color pixelCPX2 may be a green pixel, the second color filter CF2 may include agreen color filter material.

The third color filter CF3 may include a color filter material disposedbetween the third color pixel CPX3 and the upper substrate UPL andselectively transmitting light of a third color generated in the thirdcolor pixel CPX3. For example, in a case that the third color pixel CPX3may be a blue pixel, the third color filter CF3 may include a blue colorfilter material.

The light blocking pattern LBP may be disposed among the first to thirdcolor filters CF1, CF2, and CF3. For example, the light blocking patternLBP may be disposed on one surface of the upper substrate UPL to facethe second bank BNK2, and may overlap an edge of each of the first tothird color filters CF1, CF2, and CF3. The light blocking pattern LBPmay be opened in a region corresponding to each light emitting area EMA.

The light blocking pattern LBP may include at least one black matrixmaterial (for example, at least one light blocking material currentlyknown) of various types of black matrix materials, a color filtermaterial of a specific or predetermined color, and/or the like withinthe spirit and the scope of the disclosure. For example, the lightblocking pattern LBP may be formed of the same or similar material asthe second bank BNK2, but is not limited thereto. For example, the lightblocking pattern LBP and the second bank BNK2 may include the same ordifferent materials.

In an embodiment, the light blocking pattern LBP may including openingOPN of a uniform size (for example, a uniform area) on the pixels PXLforming each pixel unit PXU, regardless of the color of each pixel PXL.In an embodiment, the light blocking pattern LBP may have openings OPNof different sizes (for example, different areas) on the pixels PXLaccording to the color of the pixels PXL forming each pixel unit PXU.

In an embodiment, a predetermined filler having a relatively lowrefractive index may be filled in a space between a lower panel of thedisplay panel PNL including the base layer BSL and the display layer DPLand an upper panel of the display panel PNL including the uppersubstrate UPL and the light control layer LCP so that the light emittedfrom the light emitting elements LD may be smoothly emitted the upwarddirection of the pixels PXL. In an embodiment, the space between thelower panel and the upper panel of the display panel PNL may be filledwith an air layer.

Meanwhile, FIG. 11A discloses an embodiment in which the upper substrateUPL may be disposed on the base layer BSL on which the pixels PXL may bedisposed, but the disclosure is not limited thereto. For example, thecolor filter layer CFL and the light blocking pattern LBP may be formedor disposed on one or a surface of the base layer BSL on which thepixels PXL may be disposed, and one surface of the base layer BSL may beencapsulated using a thin film encapsulation layer, or the like withinthe spirit and the scope of the disclosure.

Referring to FIG. 11B, the first, second, and third color pixels CPX1,CPX2, and CPX3 may include the light emitting elements LD that emitlight of the same color. For example, all of the first color, the secondcolor, and the third color pixels CPX1, CPX2, and CPX3 include the thirdcolor light emitting elements LDb (for example, blue light emittingelements) that emit light of blue. For example, the third color lightemitting elements LDb may emit blue light belonging to a wavelength bandin a range of about 400 nm to about 500 nm.

In this case, a color conversion pattern layer CCL including at leastone type of color conversion particles may be disposed on the firstcolor and the second color pixels CPX1 and CPX2. Accordingly, thedisplay device according to an embodiment may display a full-colorimage.

For example, the light control layer LCP may include the colorconversion pattern layer CCL (and/or a light scattering layer LSL) andthe color filter layer CFL disposed on one surface of the uppersubstrate UPL to face the pixels PXL. The color conversion pattern layerCCL may be disposed between the color filter layer CFL and the pixelsPXL, and may include color conversion particles.

By way of example, the light control layer LCP may include a first lightcontrol layer LCP1 disposed on the first color pixel CPX1, a secondlight control layer LCP2 disposed on the second color pixel CPX2, and athird light control layer LCP3 disposed on the third color pixel CPX3.For example, the first, second, and third light control layers LCP1,LCP2, and LCP3 may include color conversion pattern layers CCL (or lightscattering layers LSL) and/or color filters CF corresponding to apredetermined color, respectively.

For example, the first light control layer LCP1 may include a firstcolor conversion pattern layer CCL1 including first color conversionparticles corresponding to the first color, and a first color filter CF1that selectively transmits the light of the first color. Similarly, thesecond light control layer LCP2 may include a second color conversionpattern layer CCL2 including second color conversion particlescorresponding to the second color, and a second color filter CF2 thatselectively transmits the light of the second color. The third lightcontrol layer LCP3 may include at least one of the light scatteringlayer LSL including light scattering particles SCT, and a third colorfilter CF3 that selectively transmits the light of the third color.

In an embodiment, the first color conversion pattern layer CCL1, thesecond color conversion pattern layer CCL2, and the light scatteringlayer LSL may be formed or disposed on one or a surface of the uppersubstrate UPL on which the first, second, and third color filters CF1,CF2, and CF3 and the light blocking pattern LBP may be disposed. Forexample, a protective layer PRL may be disposed on a surface of thefirst color conversion pattern layer CCL1, the second color conversionpattern layer CCL2, and the light scattering layer LSL.

According to an embodiment, a pattern capable of blocking light may beadditionally disposed between the first color conversion pattern layerCCL1, the second color conversion pattern layer CCL2, and the lightscattering layer LSL. For example, the light blocking pattern LBP mayhave a multi-layer structure including a first light blocking patternLBP1 interposed between the first, second, and third color filters CF1,CF2, and CF3, and a second light blocking pattern LBP2 interposedbetween the first color conversion pattern layer CCL1, the second colorconversion pattern layer CCL2, and the light scattering layer LSL.

Meanwhile, an embodiment of FIG. 11B shows the display panel PNL of astructure in which the second light blocking pattern LBP2 may be firstformed or disposed on one or a surface of the upper substrate UPL andthen the first color conversion pattern layer CCL1, the second colorconversion pattern layer CCL2, and the light scattering layer LSL may beformed or disposed, but an order of forming the second light blockingpattern LBP2 may be changed. For example, in an embodiment, the firstcolor conversion pattern layer CCL1, the second color conversion patternlayer CCL2, and the light scattering layer LSL may be first formed ordisposed on one or a surface of the upper substrate UPL on which thecolor filter CF or the like may be disposed, and then the second lightblocking pattern LBP2 may be formed or disposed. For example, the orderforming the first color conversion pattern layer CCL1, the second colorconversion pattern layer CCL2, the light scattering layer LSL, and thesecond light blocking pattern LBP2 may vary according to performance, amanufacturing method, or the like of equipment used to form the firstcolor conversion pattern layer CCL1, the second color conversion patternlayer CCL2, and the light scattering layer LSL.

In an embodiment, the first light blocking pattern LBP1 and the secondlight blocking pattern LBP2 may be integrated. For example, the firstlight blocking pattern LBP1 may be formed or disposed in a thickness (ora height) sufficient to be positioned between the first color conversionpattern layer CCL1, the second color conversion pattern layer CCL2, andthe light scattering layer LSL. For example, the light blocking patternLBP may be formed as a single layer or multiple layers, and a structure,a position and/or a height thereof may be variously changed.

The first color conversion pattern layer CCL1 may be disposed on thefirst color pixel CPX1 and may convert the light of the third coloremitted from the third color light emitting elements LDb into the lightof the first color. To this end, the first color conversion patternlayer CCL1 may be disposed between the third color light emittingelements LDb and the first color filter CF1, and may include first colorconversion particles. For example, in a case that the third color lightemitting elements LDb disposed on the first color pixel CPX1 may be bluelight emitting elements emitting the light of blue and the first colorpixel CPX1 may be a red pixel, the first color conversion pattern layerCCL1 may include a red quantum dot QDr that converts the light of blueemitted from the third color light emitting elements LDb into light ofred. In this case, the first color filter CF1 may be a red color filter.

The red quantum dot QDr may absorb blue light, shift a wavelengthaccording to an energy transition, and emit red light of a wavelengthrange of about 620 nm to about 780 nm. Meanwhile, in a case that thefirst color pixel CPX1 may be a pixel of a different color, the firstcolor conversion pattern layer CCL1 may include a first quantum dotcorresponding to the color of the first color pixel CPX1.

The second color conversion pattern layer CCL2 may be disposed on thesecond color pixel CPX2 and may convert the light of the third coloremitted from the third color light emitting elements LDb into the lightof the second color. To this end, the second color conversion patternlayer CCL2 may be disposed between the third color light emittingelements LDb and the second color filter CF2, and may include secondcolor conversion particles. For example, in a case that the third colorlight emitting elements LDb disposed on the second color pixel CPX2 maybe blue light emitting elements emitting the light of blue and thesecond color pixel CPX2 may be a green pixel, the second colorconversion pattern layer CCL2 may include a green quantum dot QDg thatconverts the light of blue emitted from the third color light emittingelements LDb into the light of green. In this case, the second colorfilter CF2 may be a green color filter.

The green quantum dot QDg may absorb blue light, shift a wavelengthaccording to an energy transition, and emit green light of a wavelengthrange of about 500 nm to about 570 nm. Meanwhile, in a case that thesecond color pixel CPX2 may be a pixel of a different color, the secondcolor conversion pattern layer CCL2 may include a second quantum dotcorresponding to the color of the second color pixel CPX2.

The light scattering layer LSL may be disposed on the third color pixelCPX3. For example, the light scattering layer LSL may be disposedbetween the third color light emitting elements LDb and the third colorfilter CF3 of the third color pixel CPX3. Meanwhile, the lightscattering layer LSL may be omitted according to an embodiment.

According to an embodiment, in a case that the third color lightemitting elements LDb disposed in the third color pixel CPX3 may be bluelight emitting elements emitting the light of blue and the third colorpixel CPX3 may be a blue pixel, the light scattering layer LSL may beselectively provided to efficiently utilize the light emitted from theblue light emitting elements. The light scattering layer LSL may includeat least one type of light scattering particles SCT. At this time, thethird color filter CF3 may be a blue color filter.

The light scattering layer LSL may include a plurality of lightscattering particles SCT dispersed in a predetermined matrix material.For example, the light scattering layer LSL may include the lightscattering particles SCT such as titanium dioxide TiO₂ or silica, but isnot limited thereto. Meanwhile, the light scattering particles SCT maynot be disposed on the third color pixel CPX3. For example, the firstand/or second color conversion pattern layers CCL1 and/or CCL2 may alsoselectively include the light scattering particles SCT.

In an embodiment, the light of blue having a relatively short wavelengthin a visible region may be incident on each of the red quantum dot QDrand the green quantum dot QDg to increase an absorption coefficient ofthe red quantum dot QDr and the green quantum dot QDg. Accordingly,finally, efficiency of the light emitted from the first color pixel PXL1and the second color pixel PXL2 may be increased, and excellent colorreproducibility may be secured. For example, manufacturing efficiency ofthe display device may be increased by forming the light emitting unitEMU of the first color, second color, and third color pixels CPX1, CPX2,and CPX3 using the of light emitting elements LD (for example, the bluelight emitting elements) of the same color.

According to an embodiment of FIG. 11B, the pixels PXL and the displaydevice having the same may be easily manufactured using the lightemitting elements LD (for example, the blue light emitting elements) ofa single color. For example, the color conversion layer CCL may bedisposed on at least some or a predetermined number of the pixels PXL tomanufacture the pixel unit PXU of a full-color and the display devicehaving the same.

FIGS. 12A and 12B are schematic cross-sectional views illustrating thedisplay device according to an embodiment, respectively. For example,FIGS. 12A and 12B show schematic cross-sectional views of the displaypanel PNL based on a region in which one first pixel unit PXU1 and asecond pixel unit PXU2 may be disposed, respectively. For example, FIGS.12A and 12B respectively show schematic cross-sectional viewscorresponding to a line III˜III′ and a line IV˜IV′ of FIGS. 9A and 9Bwith respect to the first pixel PXL1 and the second pixel PXL2 to showthat the light blocking pattern LBP is opened by different areas (forexample, different lengths and/or widths) on the first pixels PXL1 andthe second pixels PXL2.

Referring to FIGS. 2 to 12B, the light blocking pattern LBP may beopened to have a first opening OPN1 on each first pixel PXL1, and may beopened to have a second opening OPN2 having the area less than that ofthe first opening OPN1 on each second pixel PXL2. Accordingly, the lightblocking pattern LBP may have a relatively narrow width in an outerregion (and/or a peripheral region thereof) AR1 of the first pixelsPXL1, and may have a relatively wider width in an outer region (and/or aperipheral region thereof) AR2 of the second pixels PXL2.

For example, the first color first pixel CPX11 may include the firstcolor light emitting elements LDr of a first number, and the first colorsecond pixel CPX21 may include the first color light emitting elementsLDr of a second number greater than the first number. In this case, thelight blocking pattern LBP may be opened on the first color second pixelCPX21 by the area less than that on the first color first pixel CPX11.Accordingly, the first color second pixel CPX21 may have an apertureratio less than that of the first color first pixel CPX11, a luminancedeviation of the first color first pixel CPX11 and the first colorsecond pixel CPX21 according to the number deviation of the first colorlight emitting elements LDr may be reduced or canceled.

In an embodiment, as shown in FIG. 12B, in a case that the lightblocking pattern LBP has the multi-layer structure including the firstlight blocking pattern LBP1 and the second light blocking pattern LBP2,the aperture ratio of the first and/or second pixels PXL1 and/or PXL2may be adjusted by adjusting an aperture ratio of at least one of thefirst and second light blocking patterns LBP1 and LBP2. For example, thearea of the second openings OPN2 may be reduced by reducing the openingarea of the first light blocking pattern LBP1 on each second pixel PXL2.Accordingly, the aperture ratio of the second pixels PXL2 may bereduced. Meanwhile, in an embodiment, the area of the second openingsOPN2 may be reduced by reducing the opening area of the second lightblocking pattern LBP2 or reducing the opening areas of both of the firstand second light blocking patterns LBP1 and LBP2, on the second pixelsPXL2. In this case, in each second opening OPN2, the formation areas ofthe first and second color conversion pattern layers CCL1 and CCL2 andthe light scattering layer LSL may be reduced.

Meanwhile, in the above-described embodiment, in order to reduce orprevent the luminance deviation of the first and second pixels PXL1 andPXL2, the aperture ratio of the second pixels PXL2 is reduced, but thedisclosure is not limited thereto. For example, the luminance deviationof the first and second pixels PXL1 and PXL2 may be reduced or preventedby maintaining the aperture ratio of the second pixels PXL2 andincreasing an aperture ratio of the first pixels PXL1. Alternatively,the luminance deviation of the first and second pixels PXL1 and PXL2 maybe reduced or prevented by adjusting the aperture ratio of both of thefirst and second pixels PXL1 and PXL2.

Although the disclosure has been described in detail in accordance withthe above-described embodiments, it should be noted that theabove-described embodiments are for the purpose of description and notof limitation. In addition, those skilled in the art may understand thatvarious modifications are possible within the spirit and scope of thedisclosure.

The scope of the disclosure is not limited to the details described inthe detailed description of the specification, but should be defined bythe claims. In addition, it is to be construed that all changes ormodifications derived from the meaning and scope of the claims andequivalents thereof are included in the scope of the disclosure.

What is claimed is:
 1. A display device comprising: at least one firstpixel each including a first light emitting area in which first lightemitting elements are arranged; at least one second pixel each includinga second light emitting area in which second light emitting elements arearranged; a light blocking pattern disposed on the at least one firstpixel and the at least one second pixel to overlap a peripheral area ofthe first light emitting area and the second light emitting area, thelight blocking pattern including: a first opening corresponding to thefirst light emitting area of the at least one first pixel; and a secondopening corresponding to the second light emitting area of the at leastone second pixel; and a color filter including: a first color filterpattern disposed in the first opening of the light blocking pattern; anda second color filter pattern disposed in the second opening of thelight blocking pattern, wherein the at least one second pixel includes agreater number of the second light emitting elements than a number ofthe first light emitting elements of the at least one first pixel, andthe second opening of the light blocking pattern has an area smallerthan an area of the first opening of the light blocking pattern.
 2. Thedisplay device according to claim 1, wherein each of the first openingand the second opening of the light blocking pattern has a shapeextending along a first direction, and the second opening of the lightblocking pattern has a length shorter than a length of the first openingof the light blocking pattern in the first direction.
 3. The displaydevice according to claim 2, wherein the first color filter pattern andthe second color filter pattern have a same color and have a shapeextending along the first direction, and the second color filter patternhas a length shorter than a length of the first color filter pattern inthe first direction.
 4. The display device according to claim 1, whereinthe second color filter pattern has an area smaller than an area of thefirst color filter pattern.
 5. The display device according to claim 1,wherein the first light emitting elements and the second light emittingelements emit light of a same color.
 6. The display device according toclaim 5, further comprising: a first color conversion pattern layerdisposed on the at least one first pixel and the at least one secondpixel and including first color conversion particles that convert lightemitted from the first light emitting elements and the second lightemitting elements into light of a first color.
 7. The display deviceaccording to claim 1, wherein the at least one first pixel includes aplurality of first pixels including first light emitting elementsarranged in each first light emitting area of the plurality of firstpixels; and the at least one second pixel includes a plurality of secondpixels including second light emitting elements arranged in each secondlight emitting area of the plurality of second pixels.
 8. The displaydevice according to claim 7, wherein the plurality of first pixelsinclude at least one first color first pixel, at least one second colorfirst pixel, and at least one third color first pixel, and the pluralityof second pixels include at least one first color second pixel, at leastone second color second pixel, and at least one third color secondpixel.
 9. The display device according to claim 8, wherein the firstcolor second pixel includes second light emitting elements of a greaternumber than a number of first light emitting elements arranged in thefirst color first pixel, and the light blocking pattern includes anopening of a smaller area on the first color second pixel than anopening of an area on the first color first pixel.
 10. The displaydevice according to claim 1, further comprising: at least one pixelblock including a plurality of pixels arranged along a second direction,wherein the at least one pixel block includes: first pixels disposed atends of the at least one pixel block; and second pixels disposed betweenthe first pixels disposed at the ends of the at least one pixel block inthe second direction.
 11. The display device according to claim 10,wherein the at least one pixel block includes a plurality of pixelblocks, and the display device comprises a display area in which theplurality of pixel blocks are arranged.
 12. The display device accordingto claim 10, wherein the light blocking pattern comprises: firstopenings disposed on each of the first pixels; and second openingsdisposed on each of the second pixels and having an area smaller than anarea of each of the first openings of the light blocking pattern. 13.The display device according to claim 10, wherein the color filtercomprises: a first color first color filter pattern disposed on a firstcolor first pixel among the first pixels; and a first color second colorfilter pattern disposed on a first color second pixel among the secondpixels.
 14. The display device according to claim 13, wherein the firstcolor second color filter pattern has an area smaller than an area ofthe first color first color filter pattern.